UNITED STATES OF
AMERICA
FOOD AND DRUG
ADMINISTRATION
CENTER FOR DEVICES AND
RADIOLOGICAL HEALTH
MEDICAL DEVICES ADVISORY COMMITTEE
ORTHOPEDIC AND
REHABILITATION DEVICES PANEL
OPEN SESSION
THURSDAY, DECEMBER
11, 2003
The
Panel met at 9:00 a.m. in the Walker/Whetstone Rooms of the Gaithersburg
Holiday, Two Montgomery Village Avenue, Gaithersburg, Maryland, Dr. Michael J.
Yaszemski, Chairman, presiding.
PRESENT:
MICHAEL J. YASZEMSKI, M.D., PhD. Chairman
EDWARD Y. CHENG, M.D. Consultant (Deputized)
FERNANDO G. DIAZ, M.D., PhD. Voting Member
(Deputized)
MAUREEN A. FINNEGAN, M.D. Voting Member
KINLEY LARNTZ, PhD. Voting Member
STEPHEN LI, PhD. Voting Member
SANJIV H. NAIDU, M.D., PhD. Voting Member
SALLY MAHER, ESQ. Industry Representative
CRISSY E. WELLS, R.T., M.B.A., M.H.S.A. Consumer
Representative
JANET L. SCUDIERO, M.S. Acting Executive
Secretary
FDA REPRESENTATIVES:
JODI H. ANDERSON
MARK N. MELKERSON, M.S.
MARJORIE SHULMAN
CELIA WITTEN, M.D.
BARBARA C. ZIMMERMAN
INDUSTRY PRESENTERS:
MICHEL LEROUX, PhD.
SCOTT G. TROMANHAUSER, M.D.
ROBERT ZOLETTI
A-G-E-N-D-A
Call to Order 4
Conflict of Interest and Deputization to Voting
Members Status 5
Welcome remarks and introduction of panel 8
Update since the August 2001 Panel Meeting 11
FDA presentation 16
Industry Presentation
Mr. Robert Zoletti 40
Dr. Scott Tromanhauser 58
Dr. Michel Leroux 89
Panel discussion
Dr. Fernando Diaz 103
General Discussion 107
Reclassification Questionnaire 188
P-R-O-C-E-E-D-I-N-G-S
8:59
a.m.
MS.
SCUDIERO: Good morning, everyone. We are ready to begin this meeting of the Orthopedic
and Rehabilitation Devices Panel. I'm Jan Scudiero, I'm the Acting Exec Secretary for this Panel,
I'm a reviewer in the Division of General and Restorative and Neurological
Devices.
Mr.
Hany Demian is the Executive Secretary for this Panel, and he is on detail
right now to another part of the agency.
First
some housekeeping matters. If you
haven't signed the attendance sheets at the doors, please do so. The agenda information for this meeting is
at these tables.
Advisory
Committee website information on upcoming meetings, summary minutes, and
transcripts, are also on these tables.
I want to announce, now, the tentatively scheduled meetings for the
Orthopedic and Rehabilitation Devices Panel for the year 2004.
You
may wish to jot these down. They are
March 22nd, and 23rd; June 3rd and 4th; August 12th and 13th; and December 2nd
and 3rd. Remember, these are
tentatively scheduled, in case we need the times.
Before
I turn the meeting over to Dr. Yaszemski I'm required to read two statements
into the record, the Temporary Voting Member Statement, and the Conflict of
Interest Statement.
First the Temporary Voting Member status. Pursuant to the authority granted under the Medical Devices
Advisory Committee Charter, dated October 27th, 1990, and amended April 20th,
1995, I appoint the following as voting members of the Orthopedic and
Rehabilitation Devices Panel, for the duration of this meeting on December
11th, 2003; Dr. Edward Cheng, and Dr. Fernando Diaz.
For
the record, these people are special government employees, and are consultants
to this panel, or another panel, under the Medical Devices Advisory
Committee. They have undergone the
customary Conflict of Interest Review, and have reviewed the materials to be
considered at this meeting.
This
was signed by Dr. David W. Feigal, Director, Center for Devices and
Radiological Health, on December 2nd, 2003.
And
now the Conflict of Interest Statement.
The following announcement addresses conflict of interest issues
associated with this meeting, and is made part of the record to preclude even
the appearance of an impropriety.
To
determine if any conflict existed the Agency review of the submitted agenda for
this meeting, and all financial interests reported by the Committee participants.
The
Conflict of Interest statutes prohibit special government employees from
participating in matters that could affect their, or their employer's,
financial interests.
The
Agency has determined, however, that the participation of certain members and
consultants, the need for whose services outweighs the potential conflict of
interest involved, is in the best interest of the government.
Therefore
a waiver was granted for Dr. Kinley Larntz, for his financial interests in
firms at issue that could potentially be affected by the Panel's
recommendations.
The
waiver allows him to participate fully in today's deliberations. Copies of this waiver may be obtained from
the Agency's Freedom of Information office, room 12-A-15 of the Parklawn
building.
We
would like to note, for the record, that the Agency took into consideration
other matters regarding Doctors Edward Cheng, Maureen Finnegan, and Steven
Li. These panelists reported current or
past interests involving firms at issue, but in matters that are not related to
today's agenda.
The
Agency has determined, therefore, that these panelists may participate fully in
the deliberations. In the event that
the discussions involve any other products or firms not already on the agenda,
for which an FDA participant has a financial interest, the participant should
excuse himself, or herself, from such involvement. An exclusion will be noted for the record.
With
respect to all other participants we ask, in the interest of fairness, that all
persons making statements, or presentations, disclose any current or previous
financial involvement with any firm whose products they may wish to comment
upon.
And
now I turn the meeting over to Dr. Yaszemski.
CHAIR YASZEMSKI: Thank you,
Ms. Scudiero. Good morning,
everybody. My name is Dr. Michael
Yaszemski, I'm an orthopedic surgeon. I
work at the Mayo Clinic in Rochester, Minnesota, with a special interest in
orthopedics or spine surgery. I'm also
a chemical engineer with a special interest in tissue engineering.
I'd
like to note, for the record, that the voting members present constitute a
quorum, as required by 21CFR14. At this
meeting the Panel will be making a recommendation to the Food and Drug
Administration on an FDA initiated reclassification proposal to reclassify the
intervertebral body fusion device, also called a cage, intended for spinal
fusion procedures in a skeletally mature adult, with a generative disk disease
at one or two levels, from C2 through C7, and L2 through S1, using autogenous
bone graft.
This
proposed device identification does not include, for consideration, combination
products, such as the intervertebral fusion device using morphogenetic
proteins, and scaffolds.
Before
we begin the meeting I would like to ask our distinguished panel members, who
are generously giving their time to help the FDA in the matter being discussed
today, and other FDA staff seated at this table, to introduce themselves.
When
your turn comes please state your name, your area of expertise, your position,
your institution, and your status on the panel, whether as a voting member, a
deputized voting member, a consumer representative, or industry representative.
I'd
like to start to my left. Dr. Naidu?
DR.
NAIDU: My name is Sanjiv Naidu, I'm an
orthopedic surgeon, and also material scientist. I'm an associate professor at Penn State College of Medicine, I'm
a voting panel member.
CHAIR
YASZEMSKI: Thank you. Dr. Larntz
DR.
LARNTZ: I'm Kinley Larntz, I'm a
statistician, Professor Emeritus, University of Minnesota. I also work as an independent consultant,
and I'm a voting panel member.
CHAIR
YASZEMSKI: Thank you. Ms. Wells?
MS.
WELLS: My name is Cris Wells, I'm the
Director of Clinical Operations at the Translational Genomics Research
Institute in Phoenix, Arizona. I am the
consumer rep on this panel.
CHAIR
YASZEMSKI: Thank you. Ms. Maher?
MS.
MAHER: Sally Maher, I'm the Senior
Director of Regulatory Affairs and Clinical Research for Smith Nephew
Endoscopy, and I'm the industry rep on this panel.
CHAIR
YASZEMSKI: Thank you. Dr. Witten?
DR.
WITTEN: Celia Witten, the division
director of the Reviewing Division at FDA for these products.
CHAIR
YASZEMSKI: Thank you. Dr. Cheng?
DR.
CHENG: My name is Edward Cheng, I'm a
professor at the University of Minnesota, the area of practice is orthopedic
oncology and joint reconstruction.
CHAIR
YASZEMSKI: Thank you. Dr. Finnegan?
DR.
FINNEGAN: Maureen Finnegan, I'm an
associate professor at UT Southwestern in Dallas. My areas of expertise are fracture in sports, and I'm a voting
panel member.
CHAIR
YASZEMSKI: Thank you. Dr. Li?
DR.
LI: My name is Steven Li, I'm the
President of Medical Device Testing Innovation in Sarasota, Florida. And my areas of interest are biomaterials,
bioengineering, and testing.
CHAIR
YASZEMSKI: Thank you. Dr. Diaz?
DR.
DIAZ: My name is Fernando Diaz, I'm a
neurosurgeon with a special interest in spine reconstruction. I'm professor of neurosurgery at Wayne State
University, and I am the senior VP for medical affairs at the Detroit Medical
Center.
CHAIR
YASZEMSKI: Thank you, Dr. Diaz. Next, Ms. Barbara Zimmerman, Chief,
Orthopedic Devices Branch, will update the Panel on several matters related to
the Panel, since the last meeting of the Panel on August 2001. Ms. Zimmerman?
MS.
ZIMMERMAN: Thank
you. I'm going to go through a list of
the -- we haven't had an update in quite some time, so I'm going to go through
the list of previous Advisory meetings, and what has come of those devices that
were discussed at the previous meetings.
On
November 20th, 2002 Panel meeting, the Independence iBOT 3000 Mobility System
was reviewed at that time, and the FDA approved that device on August 13th,
2003.
On
August 9th, 2001, the Ascension Metacarpal Flangial Finger Joint was reviewed
at that time, and approved on November 19th, 2001.
On
January 10th, 2002, the Infused Bone Graft with LT-Cage for lumbar tapered
fusion was reviewed and approved on July 2nd, 2002.
At
a panel meeting that occurred some time between 1997 and 2000, I actually
couldn't find the exact date of this panel meeting, a PDP was discussed for the
Encore Keramos Ceramic on Ceramic Hip System.
This PDP was approved on November 26th, 2003.
At
a July 20th, 2000 panel meeting the Osteonics ABC System and the Trident
System, which is a ceramic on ceramic hip system, was approved on February 3rd,
2003.
We
have had several recent reclassification actions. The reclassification petition for Mobile Bearing Knees has been
submitted by OSMA on June 13th, 2003, and is under review by the Agency at this
time.
There
was a reclass, the metal on polymer porous coated uncemented femoral knee joint
prostheses, and unicompartmental metal on polymer uncemented femoral tibular
knee joint prostheses were reclassified into class 2, on March 24th, 2003, and
this was published in the Federal Register.
The
Reclassification Petition for metal on metal total hip hiparthroplasty devices,
which was reviewed at the August 8th, 2001 panel meeting was denied on
September 6th, 2002. However, the FDA
continues to work with OSMA, and hopes that a subsequent petition will be
submitted at a later date.
The
metal on polymer constrained hip joints were reclassified into Class 2 on April
2nd, 2002. And then resorbable calcium
salt bone void filler was classified into Class 2 on June 2nd, 2003.
There
is a 510(k) clearance that I would like to bring to your attention. This is for the DePuy Delta Shoulder. It was cleared on November 18th, 2003. It is designed such that the ball of the
articulation is incorporated into the glenoid prostheses, and the cup of the
articulation is incorporated into the humoral prosthesis, i.e., a reversed
shoulder. It is indicated for patients
with rotator cuff deficient shoulder joints.
That
is all I have, thank you.
CHAIR
YASZEMSKI: Thank you, Ms. Zimmerman.
Today
we will begin with the FDA presentation, then we will hear two industry
presentations, and then proceed to the open public hearing.
We
will next have the Panel deliberation portion of the meeting, beginning with an
introduction of today's topic, that will be led by Dr. Diaz. After having a general discussion the Panel
will address the FDA questions, then the Office of Device Evaluation,
Classification, Reclassification coordinator will guide the Panel in the
completion of two forms.
One,
the reclassification questionnaire, and two, the supplemental work sheet. The Panel's vote on these two documents will
constitute our recommendations to the FDA.
We
ask, at this time, that all persons addressing the Panel speak clearly into the
microphone, as the transcriptionist is dependent on these means to provide an
accurate record of the meeting.
And
I will ask your indulgence if during your talk you haven't done that, and I
will gently remind you to do so. So
please bear with me if I do that.
We
are also requesting that persons making statements during the open public
hearing clearly state his or her name, affiliation, and the nature of any
financial interest he or she may have in this, or another medical device
company, if any, and disclose if anyone, besides yourself, paid for your
transportation and accommodations to this meeting.
I'd
like to remind public attendees at this meeting that while the meeting is open
for public observation, public attendees may not participate except at the
specific request of the Panel.
We
will now have the FDA presentation on the proposed reclassification. The FDA presenter is Ms. Jodi Anderson, a reviewer
in the Orthopedics Device Branch.
Ms.
Anderson?
MS.
ANDERSON: Good
morning. Thank you all for being here
this morning. I'm going to present an
FDA-initiated proposal for the reclassification of intervertebral body fusion
devices.
And
from this point forth, for the case of simplicity, I'm just going to refer to
these devices as cages.
Let
me begin with an anecdote. Last night
my husband and I were eating Chinese food. At the end of the meal we received
fortune cookies and, I think, as an accepted means of choosing the fortune
cookie, I chose the fortune that was pointed my way.
Opening
the cookie it says, you will make a change for the better. I digress and point out that my lucky
numbers are 1, 12, 23, 38, 40 and 25.
Anyway,
let me move on. This morning I'm going
to discuss four major topics. I'm going
to present a background of medical device classification. The Panel has just heard this, but for
everybody in the audience perhaps this will be helpful.
I'm
going to give a regulatory history of cages.
I'm going to give an FDA initiated cage reclassification proposal, and
then I'm going to go through, briefly, the questions for the Panel.
And
at this time, actually, the Panel is not going to be commenting on these
questions, I'm just providing them so that you have a heads up as to what you
will be discussing shortly.
Medical
device classification, where did it come from?
The 1976 amendments of the Food, Drug and Cosmetic Act, provide
regulations for the classification and regulation of medical devices intended
for human use.
The
Act established three categories, or classes, of medical devices depending upon
the regulatory controls needed to provide a reasonable assurance of their
safety and effectiveness.
There
are Class I devices, which require general controls; Class II devices, which
require special controls; Class III devices, which require pre-market
approval.
I'm
going to describe what each of these controls are in the next couple of
slides. What are general controls? General controls provide a means of ensuring
the reasonable safety and effectiveness of Class I devices.
General
controls include things like prohibition against adulterated or misprinted
devices, pre-market notification/submissions, or 510(k)s, the quality system
regulations, which includes design controls, good manufacturing processes, or
GMPs, and registration of manufacturing facilities.
What
are special controls? Well, in the
instance that general controls are insufficient, special controls are added to
provide the reasonable assurance of safety and effectiveness of Class II
devices.
Special
controls include things like Guidance Documents, Performance Standards,
Post-Market Surveillance, Clinical Data, and Labeling. And special controls are going to be the
focus of much of our later discussion, or much of my later discussion.
Class
III devices are life sustaining, or life supporting or, particularly, in the
instance of orthopedic devices, present an unreasonable risk for causing illness
or injury.
Insufficient
information exists to determine the adequacy of general and special
controls. So Class III devices are
regulated by using valid scientific evidence presented within a pre-market
approval application, or PMA, to establish the safety and effectiveness of the
device.
I
could go on to a long discourse regarding what consists a valid scientific
evidence, and what does not, but I think that that would confuse this
discussion. And if you have that
question feel free to bring it up with me later.
So,
reclassification, the FDA can change the class of a medical device to a
different regulatory class. In fact,
FDA is required to clarify and reclassify devices into the lowest class that
can reasonably assure the safety and effectiveness of the device.
I
wish I could just say S&E, but that would be confusing. When can a device be reclassified? A Class III device can be reclassified when
FDA can identify the risks associated with the device, and the manner in which
these risks can be controlled by general and special controls.
And
while we are doing this we hope to maintain a least burdensome approach. So let me get into cages. Having reviewed regulatory background, I
will move on to describe the devices for which propose the reclassification.
So
we consider cages to be implanted single or multiple component spinal devices
made from a variety of materials, for example, titanium alloys or polymers,
that fill the intervertebral disk space, for example, hollow threaded
cylinders, mesh cylinders, fenestrated rectangular blocks, trapezoidal cubes,
or wedge shaped solids, and they are available in a variety of sizes.
The
following describe the approved indications for use of cages. They are approved for the following
indications, skeletally mature patients with degenerative disc disease, also
known as DDD.
DDD
is defined as discogenic back pain, with degeneration of the disc, confirmed by
patient history, and radiographic studies.
The patients can also have up to grade 1 spondylolisthesis, or
retrolisthesis, at the involved level.
Let
me make an important note. Each of the
currently marketed cages has its own indications for use. The above simply lists all the indications
which are currently legally marketed.
The
following are the intended uses which have been approved for cages. Spinal intervertebral body fusion
procedures, at one or two levels, between C2 and C7, or L2 and S1. They are used with or without supplemental
fixation.
They
are used with autogenous bone graft, and they are implanted by a laprascopic
and open posterior approach, or an open anterior approach. Again, let me point out that each of the
currently marketed cages has its own set of intended uses. Again, the above list simply lists all the
intended uses which are legally marketed.
So
how are cages classified? Cages were
first marketed in the U.S. after 1976 amendments to the Food, Drug, and
Cosmetic Act. They are Class III
post-amendment devices, which require an approved PMA prior to marketing.
Since
1996 CDRH has approved seven intervertebral body fusion devices. Six have been PMA devices using autograft,
and one has been a PMA device, which is a combination product, because it
incorporates BMP with the cage.
This
is the fun part, roll call, if you will.
The following lists the cages that have received approval by the PMA
process. If your name is called, or if
your company is called, as I read this list, please feel free to stand up and
wave. Just kidding, you can just stay
seated.
This
includes the BAK, the BAK Proximity, the BAK Vista, which are manufactured by
Sulzer Spine-Tech; Ray TFC, and RAY TFC Unite, by Howmedica Osteonics; the
Lumbar I/F Cage, by DePuy Acromed Interfix, Interfix RP, LT-Cage, PEEK LT-Cage,
manufactured by Medtronic Sofamor Danek; the BAK/C, by Sulzer Medica, or Sulzer
Spine-Tech, excuse me; the Affinity, manufactured by Medtronic Sofamor Danek;
and the Infuse, which is a combination product, again, used with BMP,
manufactured by Medtronic Sofamor Danek.
In
addition to the devices I just listed, being described in marketing
applications, they have also been well described in publicly available
literature.
Because
reclassification petitions rely only upon publicly available information only
that information will be referenced in this presentation.
So
what have we learned from the literature?
We have learned about the device descriptions, the device
specifications. We have learned about
an efficacy profile, and we've learned about a safety profile, or the risks associated
with cages.
A
two year study of the Ray TFC demonstrated a 96 percent fusion rate at the two
year point, 65 percent good or excellent results, 21 percent fair, and 14
percent poor.
At
the four year time point the BAK demonstrated a 95.1 percent fusion rate. At the two year time the LT-Cage had a 93
percent successful fusion rate, and 72 percent overall patient satisfaction.
The
following point is presented clearly after looking at some of these
studies. In cases where studies are
conducted in a rigorous and well controlled fashion, results are repeatable.
That
isn't always the case. Others have not
always been able to duplicate these high success rates. In fact there have been many instances of
high complication rates, and high revision rates.
In
the Zdeblick article "Interbody Cage Devices", he states: Failures are the result of technical
difficulties and poor patient selection.
This isn't, actually, unexpected.
In fact, most medical devices require appropriate patient selection, and
detailed surgical approaches to assure optimal outcomes.
So
what have we learned about the risks?
Based on the information gathered from MDR reports, and the literature,
we have learned about the following risks associated with cages.
Device
related risks include loosening, end cap separation, extrusion, migration,
malpositioning, device fracture, deformation, and wear.
Patient
related risks include vascular injury, neurological injury, urological injury,
infection, non-union, vertebral fracture, subsidence, and end-plate collapse.
With
this information at hand FDA proposes cage reclassification. We propose the cages be reclassified from
Class III to Class II. We believe that
the risks associated with the device can be controlled by general and special
controls.
We
also believe that down classification meets the FDA mandate to apply the least
burdensome approach to device regulation.
Let me state the crux of my argument.
And if your coffee hasn't kicked in, now is the time to pay attention.
What
I've described does not imply that FDA knows all that there is to know about
cages. What we have learned to this
point leads us to believe that the risks associated with the device can be
controlled by general and special controls, and no longer need to be controlled
by a PMA.
Let
me just let that sink in for a moment.
So what special controls would we use?
Guidance documents are one of the special controls that can be used to
address risks.
We
believe that, in fact, we can develop a guidance document to address the risks
imposed by cages. And let me point out
that this guidance document has not yet been developed, and I'll refer to it in
the future as a TBD guidance document, not to be determined, but to be
developed.
The
guidance is intended to convey the Agency's current thinking on cages. It will provide the Agency's recommendations
on how to address the issues presented in the guidance.
And
let me stress this, a firm need only show that its device meets the
recommendations of the guidance, or in some other way provides equivalent
assurances of safety and effectiveness.
What
would this guidance document include?
And, again, let me stress that this is the to be developed guidance
document. It would include introduction
and background material, content and format of the submissions that would be
required.
It
would describe the scope of the guidance, a device description of the device,
the cage, labeling, and training. It
would also provide a comprehensive description of the pre-clinical testing
required in a 510(k) submission that would occur if the device were
reclassified.
This
information would include biocompatability information, sterility information,
and mechanical testing. This mechanical
testing, again, would be comprehensive and would include compression bending,
both static and dynamic, torsional testing, again, static and dynamic; shear
testing, both static and dynamic, and subsidence testing.
The
guidance document would also reference standards, material standards such as
the titanium alloy standard, or the PEEK standard. It would include biocompatability standards, ISO 10993, for
instance; and testing standards, like the most recent F2077-03, which describes
test methods for cages.
We
are quite confident in our ability to create this guidance document. And, in fact, this guidance document will be
similar in format and content to guidance documents for spinal devices that are
already available to the public. That
would include the spinal IDE guidance, and a spinal 510(k) guidance.
And
if you don't have a copy of these in your hot little hands, you can just go
over to the web, note the address, and find them.
So
in an effort to describe our thinking I will provide you with the patient
related risks associated with cages, and the manner in which we believe special
controls can be used to control these risks.
And,
again, the TBD is to be developed guidance document. So we believe that patient related risks, and I won't read
through the list again, can be mitigated by information included in this
guidance document, that would include information describing surgeon training,
product labeling, and material biocompatability.
Also
I will give you our feel about the correlation of device related risks, and the
manner in which we believe special controls can be used to control these risks.
Again,
TBD, to be developed guidance document would include things like surgeon
training to mitigate the risks, product labeling, material biocompatability,
and particularly the mechanical testing, compression bending, torsion,
subsidence. Actually expulsion isn't
supposed to be there.
I
apologize for the next two slides. In
fact my mentor, who taught me how to make slides, would be having a coronary if
he saw all of this information on one slide, but I really had no choice.
I'm
going to present to you FDA's proposal for cage reclassification. The device description. The intervertebral body fusion device is an
implanted single, or multiple component spinal device, made from a variety of
materials, including titanium alloys, for example, Ti-6AL-4V, and polymers; for
example PEEK, or Polyetheretherketone.
Such
a spinal implant assembly would consist of a construct intended to fill the
intervertebral disc space, for example, hollow threaded cylinders, mesh
cylinders, fenestrated rectangular blocks, trapezoidal cubes, or wedge shaped
solids.
The
implant is available in a range of sizes, and may be angled to fit the
patient's anatomical and physiological requirements. The implant may have a variety of features, some of which include
spiked teeth on the inferior and superior surfaces of the implant, and through
holes intended to allow bony ingrowth, and end caps.
The
intended uses and indications. The
interbody fusion device is intended for spinal fusion procedures, in skeletally
mature patients, with degenerative disc disease, DDD, at one or two levels,
from C2 to C7, and L2 to S1.
DDD
is defined as discogenic neck and back, or neck or back pain, with degeneration
of the disc confirmed by patient history, and radiographic studies.
These
DDD patients may also have up to Grade spondy, or retrolisthesis at the
involved levels. The implant is
intended to be used with autogenous bone graft, and implanted by a laprascopic
and open posterior approach, or an open anterior approach.
So
let me summarize. FDA does not know all
that there is to know about cages. We
have learned a great deal about the risks associated with cages, however, and
we believe that the risks associated with the device can be controlled by
general and special controls, and no longer need to be controlled by a PMA.
I'm
going to briefly go through the questions that are going to be posed to the
Panel, in a bit, just so you have a heads up.
Question one is going to be please discuss the descriptive information
and intended use presented in the reclassification identification.
Question
two is going to be, please discuss any specific pre-clinical testing criteria
you believe are needed to characterize the intervertebral body fusion device.
Question
three, please discuss the risks to health for the intervertebral body fusion
device. Question four, much like
question three, please discuss any other risks. And by that I mean risks that I haven't identified, or that we
haven't identified, to health, for these devices that have not been presented.
And
question five is, do you believe special controls can be developed to
adequately control the risks associated with this device?
Thank
you very much.
CHAIR
YASZEMSKI: Thanks very much, Ms.
Anderson. Does anyone on the Panel have
questions for Ms. Anderson? Dr.
Finnegan.
DR.
FINNEGAN: I know that everyone is
uncomfortable with performance standards, but could you outline for us what the
difficulties are in asking for some performance standards?
MS.
ANDERSON: I guess the difficulty with
asking for performance standards is it sets forth a criteria that everybody
need meet. At this point I think we are
open to justifications for why certain performance data are going to be
physiologically acceptable.
So
we would rather see a justification for a specific case, rather than outlining
if you meet this, this, and this, then you are okay.
DR.
FINNEGAN: Can you bear with me for a
second? If you look at total joints
with the polymers for the acetabular cups, if they had had performance
standards there might not be as many people walking around with a whole bunch
of ugly looking bones.
So
I guess that is the reason for my question, we don't know the ten year out,
particularly if you have a mixed component, well even if you just have metal,
but if you have mixed component with aging changes in the spine.
So
I guess that is my concern, how do you capture that data sooner rather than
later?
MS.
ANDERSON: I'm not certain I completely
understand your question. Are you
asking for information that describes how these devices are going to perform
ten years out or --
DR.
FINNEGAN: What I'm suggesting is that
you don't have the information. I guess
that is my translation of performance standards, is if you put in -- let me
back up for a second.
We
know if we put in metal and polyethylene, and there is significant demand on
those materials, that mix of materials, that you will get polyethylene wear on
the body response to polyethylene wear in a very specific manner, which we did
not know when we started total hips.
MS.
ANDERSON: Let me go ahead and change
your question around a little bit, because what you are asking about is
efficacy regarding cages.
And
actually what I've just presented is actually not a discussion of all the
efficacy of cages. In fact what I'm
doing, and what I am presenting, is more of a risk management proposal.
So
my proposal isn't focusing on all of, again, what I've presented is that we
don't know everything that there is to know about cages, especially if you go
out at the ten year point.
What
I'm saying is that what we know about cages today leads us to believe that we
are certain, we know of the risks that cages bring forth, and that these risks
can be mitigated using special controls, instead of using a PMA.
If
we were to approve a PMA for a cage we would still have the same questions that
you are proposing, we wouldn't know what would happen at the ten year time point.
Celia,
I see you heading towards the microphone.
Is there something you wanted to add?
DR.
WITTEN: Yes, just that -- I just want
to say that this is part of our questions for you all, to the Panel, have we
identified the risks, and can they be mitigated with the controls that we are
proposing.
DR.
FINNEGAN: And I guess my question is,
could a guidance document include those kinds of things? I don't understand, I guess, what
performance standards are separately from guidance documents.
DR.
WITTEN: Well, a performance standard is
a specific term which to us means that there is some number, you know, some
target that something absolutely has to meet in order to get on the market.
I
think we've only promulgated one in the whole history of FDA. You have to do it either by regulation or by
law.
DR.
FINNEGAN: So our concerns could be put
into a guidance document?
DR.
WITTEN: Yes. And if you know, for example, that -- I mean, what we usually do
with testing is you do testing compared to a predicate. So for the kind of test that Jodi just
listed we would look at the test results and the sponsor would compare how
their device performed compared to a predicate.
And,
you know, we would see whether those differences gave us concern about the new
device. But if there are some things
that you know that represent a target that sponsors should meet, you know, in
general unless they can provide a justification for something else, or if there
is something that we know about what the test results should be, that would
certainly be good information for us.
But
that is, you know, what we do is when we have something in the Class II is we
look at the testing, and we compare it with devices on the market to see
whether the new device will perform equivalently to the old device, on the
things that we know how to measure, which are the kind of things that Jodi just
mentioned on the list.
DR.
WITTEN: So performance standards aren't
a long term assessment?
DR.
WITTEN: No, what we look at is the guidance
would provide you a framework for making a comparative assessment of the new
device that was proposed for market, compared to the device that was already on
the market.
CHAIR
YASZEMSKI: Thank you, Dr. Witten, and
Dr. Finnegan. Dr. Naidu?
DR.
NAIDU: Mine is a more simple question,
but it does concern the guidance document.
Is the FDA proposing to develop a guidance document for metallic cages
and plastic cages separately? Or are
you going to split this at all, or are you just going to generally classify
them all under one?
MS.
ANDERSON: I think our current thinking
is the development of one guidance document and, as Dr. Witten mentioned, if
you believe that it would be necessary to create the guidance for two separate,
we would be open to hearing it.
I
think our current belief is that the testing is going to be more or less the
same regardless of the material composition, to a certain point.
So
that both PEEK cages and titanium cages would be tested similarly. For instance, with a PEEK cage you might
focus more on shear testing, the generation of wear debris, where that might
not be of concern for a titanium cage.
But
I think both of those issues could be addressed in one guidance document.
DR.
NAIDU: Thank you, Ms. Anderson.
CHAIR
YASZEMSKI: Thank you, Ms.
Anderson. Any other questions for Ms.
Anderson? Dr. Larntz??
MS.
ANDERSON: I didn't present any
statistics.
DR.
LARNTZ: But I found some things to talk
about, Jodi.
MS.
ANDERSON: Why does that not surprise
me?
DR.
LARNTZ: I just want to make sure we are
clear, or I'm clear. A guidance
document can have guidance with respect to performance.
MS.
ANDERSON: It can.
DR.
LARNTZ: And that is a very important
aspect. But it is also a guidance
document, it is not a requirement for every detail.
MS.
ANDERSON: In fact I believe I mentioned
that. I think I tried to state very
clearly that these are recommendations, and that industry can either provide
the information required, or provide a justification for that information's
omission.
DR.
LARNTZ: Right. That is all I wanted to make sure, you know,
performance standards as some of us are thinking about them I think are in
other guidance documents, for instance, throughout the Agency, but they are not
called performance standards, they are guidance.
MS.
ANDERSON: Correct. What I'm talking about is, indeed, a
guidance document. And a guidance
document is a suggestion, it is not a mandate.
CHAIR
YASZEMSKI: Thank you, Dr. Larntz. Other questions for Ms. Anderson?
MS.
ANDERSON: I will be available for
further questions later if you change your mind.
CHAIR
YASZEMSKI: Thank you, Ms.
Anderson. We are now going to have two
industry presentations. First we will
hear from representatives of the Orthopedic Surgical Manufacturers Association,
OSMA. Mr. Robert Zoletti, and Dr. Scott
Tromanhauser.
Mr.
Zoletti? Are you going to be okay,
sir? Can you go ahead as is?
MR.
ZOLETTI: It looks like
it is going to work.
Good
morning, I'm Robert Zoletti, director of clinical and regulatory affairs,
Cortek, Inc., a developer of spinal implants and instrumentation. I'm speaking today as a representative of
OSMA, the Orthopedic Surgical and Manufacturers Association.
I
didn't get any fortune cookies yesterday but I did, by joining OSMA, get the
fortune of doing this presentation. I
got that -- that was given to me because I asked about cage reclassification.
The
Orthopedic Surgical Manufacturers Association is a trade organization whose
membership consists of 29 manufacturers of orthopedic surgical appliances,
implants, instruments, equipment, and orthobiologics.
Since
its inception in 1954 OSMA has actively participated in standards development,
patient education, product labeling, guidelines, international activities, and
support of multiple reclassification petitions.
The
cooperation and interaction with FDA and health care professionals on issues
that lessen the regulatory burden and improve application of device law, and
continue to be the major objectives of OSMA.
All
the companies that hold PMAs for intervertebral body fusion devices are OSMA
members. OSMA supports reclassification
of intervertebral body fusion devices, generically known as cages, as stated in
the proposed CFR listing.
OSMA
member support for this reclassification petition has been cautious. There is some concern, among current PMA
holders, that the scope of the reclassification be narrowed during the
classification process in a manner that may not permit clearance of newer design
cages under a 510(k).
Therefore
three OSMA members that hold PMAs for interbody fusion cages are currently
withholding access to their unpublished clinical data pending the outcome of
the Panel meeting.
No
OSMA member company has opposed reclassification. The current classification language proposed by FDA is generally
supportive, and clearly allows for design beyond cylindrical titanium cages.
We
see this reclassification as part of a continued effort to appropriately
classify spinal implants. We encourage
the Panel to support the language FDA has used, in the FDA proposal, for
reclassification of the intervertebral body fusion device. I have said that enough times and it doesn't
want to come out.
This
position goes hand in hand with the least burdensome provisions of the Food and
Drug Administration Modernization Act of 1997.
There has been a long history of cages, and a long history of spinal to
body fusion procedures.
Burns
of Great Britain reported the first lumbar interbody fusion in 1933, using
autogenous bone. Posterial lumbar
interbody fusion was first performed in the early 1940s.
During
the 1970s and early 1980s Bagby managed cervical spinal instability in horses
by means of interfusion using the Bagby basked, a hollow, extensively
perforated stainless steel cylinder.
Using the Bagby basket as a foundation, the Bagby and Kuslich implant,
known as the BAK, was developed.
The
first human implants were conducted under an IDE in 1992, and the first PMA was
approved in 1996. The Bagby and Kuslich
method of lumbar interbody fusion was published in "Spine" in 1998,
reporting the results of 947 patients treated from 1992 to 1995, with chronic
discogenic low back pain, by interbody fusion using the BAK cage.
RAY
reported two year follow-up data, 208 patients, using the RAY titanium fusion
cage, in the March 1997 issue of "Spine".
Two
year results were reported by Brantigan et al, using a PEEK carbon
fiber-reinforced cage, in the June 2000 issue of "Spine".
In
all three studies fusion rates were high, between 90 and 100 percent, and
clinical outcomes were favorable, at 85 to 97 percent of patients reporting
improvement in pain, or function, compared to pre-operative levels.
These
studies resulted in the first PMAs for cages, which were approved in 1996,
seven years ago. Hundreds of thousands
of cages have been implanted in the lumbar and cervical spine throughout the
world. In the U.S. alone the number of
procedures using metal cages is a total of 145,000 since the year 2000.
As
mentioned previously fusion success with cages has been reported to be in the
range of 90 to 100 percent. Although
fusion procedures have not proven to be a cure for all patients, there is
evidence supporting the benefits of this procedure.
The
2001 Volvo Award clinical study, "Lumbar Fusion versus Non-Surgical
Treatment for Chronic Low Back Pain" by Fritzell et al., a randomized
control multi-center study concluded that lumbar fusion in a well informed and
selected group of patients with severe and therapy resistant chronic low back
pain, can diminish pain, improve function more effectively than commonly used
non-surgical treatment.
This,
which is also a very hard slide to read, is a list of, a sample list of some of
the journal articles published from cage studies.
Although
interbody fusion devices are currently regulated as Class III products, and
have required extensive clinical studies in PMA approval, other spinal implants
do not have these requirements.
FDA
currently regulates a number of implants using the spine as Class II, or
unclassified. All are reviewed via the
510(k) process. This slide is a list of
the FDA product codes and classifications for spinal implants.
These
products include pedicle screws, rods, plates, hooks, connectors, and vertebral
body replacement devices. Again, all
approved by 510(k). Recently pedicle
screw 510(k), KO31855 Spinal Concepts Insight Pedicle Screw System, was cleared
for a number of codes, including NKB, which is Class III pedicle screw system
for degenerative disc disease.
This
clearance was obtained using clinical test data, including data collected in
accordance with ASTM 1717, and ASTM 1798.
The product code shown, in the previous slide, Class II vertebral body
replacement devices, are the most notable for comparison to spinal cages.
They
are often similar in design, and materials, to interbody fusion cages. They replace the vertebral body and disc,
instead of replacing just the disc.
Fusion between the vertebrae are often possible.
Vertebral
body replacement products are cleared for thoracic and lumbar spine solely on
mechanical test data, without the need for clinical study.
This
is an example of vertebral body replacement devices, on the left, and cages on
the right. You can see the
similarities.
The
guidance document for spinal system 510(k)s, list the testing necessary to
support substantial equivalence of vertebral body replacement devices as static
compression, or compression bending, dynamic compression, or compression bending,
static torsion, dynamic torsion, and expulsion.
Additional
testing may also be necessary depending on the design of the vertebral body
replacement system. Similar test
requirements can be applied to cages.
Title
21CFR Part 860 provides for the procedures for medical device
reclassification. Section 860.130
states: The Commission may change the
reclassification from Class III to Class II if the Commission determines that
special controls, in addition to general controls, will provide reasonable assurance
of the safety and effectiveness of the device, and there is sufficient
information to establish special controls to provide assurance of safety and
effectiveness.
An
analysis of interbody fusion device adverse events has been conducted using MDR
data. The type of adverse event, and
the special controls that could address the adverse event are shown in the
slide.
The
analysis indicates that the combination of biocompatability testing, materials
standards, mechanical testing, and labeling, in combination with QSR general
controls, can address the adverse events found.
These
occurrence rates are extremely low compared to the number of implants
used. Other non-device specific events
are also addressed with controls, as shown in this slide.
Standards
that could be used to assure the safety and effectiveness of cages are
essentially those used for other Class II orthopedic spinal implants. These standards encompass, among other
things, the variety of test methods and labeling requirements.
After
more than ten years of use the risks associated with interbody fusion devices
are well known, and can be controlled by special controls such as standards
shown on the previous slides, and general controls.
OSMA
would like to voice some additional considerations for the Panel. First, OSMA would like the FDA and the Panel
to consider that posterior or internal fixation systems are often used with
cages.
We
propose that the reclassification language allow optional use of supplemental
internal fixation systems with cages.
Second, OSMA encourages the Panel, and the FDA, to consider expanding
the language to include use of allograft bone, or other approved bone
substitutes.
Under
the current approvals, PMA holders are required to complete post PMA studies. The burden of these post PMA studies should
be ended now. Next, IDEs currently
underway should be allowed to close, and sponsors should be allowed to file
final reports if the device complies with the reclassification requirements.
Also,
the current classification statement indicates use from C2 to C7 and L2 to
S1. OSMA suggests the language not
restrict spinal levels. The Panel
should be aware that the FDA has required labeling for some cage products, such
as, should only be used by surgeons who are experienced in spinal fusion
procedures, and have undergone adequate training for this device.
Another
variation is to require the phrase "appropriate training". In addition, FDA required some, if not all
companies, as a condition of PMA approval, to conduct courses as part of the
approval order.
We
strongly encourage this Panel to advise the FDA staff that the companies are
not in a position to determine when training is adequate, or appropriate, and
that companies, per se, should not be required to conduct training courses.
The
situation is particularly the case with cages where OSMA believes that the use
of cages has matured, and that surgeons now receive training with those
products by other surgeons, as part of their education.
Doctors
should train doctors, the companies should not be required to conduct training
courses. A new requirement for clinical
data should be for truly new designs that cannot be otherwise be found
substantial equivalent.
In
the infrequent situation that clinical data may be required, to demonstrate
substantial equivalence, the scope of the study should be no burdensome.
PMA
data, including available SS&E data, cannot be used at this time, by other
companies, or by the FDA to support submissions, or this reclassification,
without release by the PMA holder.
OSMA
member companies have been reluctant to open their PMA data, for public
release, to support this reclassification.
Once released this data can be used to support the approval of similar
products by other companies.
There
is concern that the reclassification may be denied, or the language may be
revised, during the clarification process to only reclassify threaded titanium
cages, an approval that several of these companies hold under the current PMAs.
The
release of data to FDA will be reevaluated after this Panel meeting, and
compose language for reclassification orders are viewed. Support for release of data is dependent on
the proposed reclassification language.
IDE
study data published in respected peer review journals, as referenced earlier,
while not providing complete information, does provide valid scientific
evidence that interbody fusion devices are safe and effective.
OSMA
supports the reclassification of interbody fusion devices under the proposed
language, and requests the Panel, and the FDA, review the additional
considerations presented above.
The
reclassification is seen as providing the same level of control required for
other spinal implants currently in use.
A reasonable assurance of safety and effectiveness can be established
through special and general controls.
Thank
you for your time.
CHAIR
YASZEMSKI: Thanks very much, Mr.
Zoletti. Do any of the Panel members
have questions for Mr. Zoletti? Dr. Li.
DR.
LI: Yes, thank you for your
presentation. On one of your early
slides you gave a little table that showed us the number of metal cage
procedures that were done since 2000?
MR.
ZOLETTI: Correct.
DR.
LI: Do you have a sense that those
numbers include revisions? In other
words, are all these primary implants, or are some of these implants revisions?
MR.
ZOLETTI: I don't know that. The data is from Millennium Research, and I
didn't see it broken out that way.
DR.
LI: Do you have any idea what the
revision, the number of implants sold for revision, is?
MR.
ZOLETTI: I don't.
DR.
LI: And the other question I have for
you is on the MDRs, in total joints we estimate that, typically, less than one
percent of implant failures are actually reported to the MDR.
Do
you have any sense for what that number is for your product?
MR.
ZOLETTI: I don't have a sense. I know these products are still under PMA
and that companies have procedures in place for submitting MDRs, as they are
reported to them.
DR.
LI: Just as kind of a back of the
envelope exercise I took your table, that you presented with the number of
implants since 2000, and I got something close to 200,000, you had a couple of
greater than.
So
I just took 200,000 just to round it off.
And if I took the best clinical series we've got there, their reparation
rate was, for device removal, was like 1.1 percent, in which case the number of
MDRs reported was actually 12 times lower than were actually reported in these
clinical series.
And
in the worse series that we got for clinical evaluations, 14 percent of 148
implants were reimplanted. And if it
was 14 percent of your 200,000, that would be 28,000 devices that have been
removed, yet there is only 183 reported in your MDR.
So
at that ratio the percent reported by the MDR is very close to what is reported
for total joints, which is less than a percent.
MR.
ZOLETTI: Okay.
CHAIR
YASZEMSKI: Dr. Finnegan?
DR.
FINNEGAN: You would like these sort of
to be considered equivalent, I'm assuming, to the vertebral body
replacements. And I'm wondering what
materials the vertebral body replacements are made of. You don't really mention that.
Are
they all metal, and are they all titanium?
MR.
ZOLETTI: I'm not familiar with all of
the products. I believe they are metal
and perhaps PEEK, but I'm not sure.
CHAIR
YASZEMSKI: Thank you, Dr.
Finnegan. Dr. Li?
DR.
LI: A follow-up question. Your table that you represented was metal
cage procedures. Do you have any
numbers for the non-metal cage procedures?
MR.
ZOLETTI: They weren't available to me.
DR.
LI: Any idea what that number is, is it
a tenth, a half, a quarter?
MR.
ZOLETTI: I would be completely
speculating. You have to ask the
companies that are doing those cages.
DR.
LI: Okay.
CHAIR
YASZEMSKI: Thanks, Dr. Li. Other questions? Dr. Larntz.
DR.
LARNTZ: Yes. You asked some additional considerations, allow the use of allograft, and other approved bone
substitutes.
I
looked at your document, which you provided, which we just got today as far as
I know. It is dated December 4th, but
it seems to have been printed on December 9th.
And
I'd like to know if there is any analysis, statistical analysis, to back up
that additional consideration?
MR.
ZOLETTI: First of all, on the dating of
the document, the document was provided to the FDA on the 4th, and I printed it
again today for you, as it had not been provided.
As
far as the statistical analysis for the additional considerations, did you
mention a specific one?
DR. LARNTZ: Additional consideration, it says, allow use with allograft bone,
and other approved bone substitutes.
MR.
ZOLETTI: So you are asking have there
been specific studies done to that?
DR.
LARNTZ: Well, if we are going to do
that I think we need some evidence to support that, if we are going to consider
it. You are asking us to consider it,
that is what I see here.
MR.
ZOLETTI: Okay. I don't have any references that I can
specifically go to, but Dr. Tromanhauser can talk about the use of that
material in his procedures.
DR.
LARNTZ: Right. I mean, I read the papers you provided, and
I didn't see any particular analysis showing equivalence, or non thereof. You also asked for expansion beyond the
levels that are used.
Again,
do you have statistical analysis that shows that the use of these devices in
other levels is basically equivalent to the ones that are proposed here?
MR.
ZOLETTI: No, I don't.
CHAIR
YASZEMSKI: Thank you. Other questions for Mr. Zoletti?
(No
response.)
CHAIR YASZEMSKI: Seeing none, we will move on.
Thank you, Mr. Zoletti.
MR.
ZOLETTI: Thank you.
CHAIR
YASZEMSKI: We will ask Dr. Tomanhauser
to come and give his presentation.
DR.
TROMANHAUSER: I brought with me a tool
that I commonly use in my office.
(Inaudible)
CHAIR
YASZEMSKI: We have to ask you, sir, to
speak into the microphone.
DR.
TROMANHAUSER: -- put your hands on
that, in a regular basis. This is a key
ring full of cages, just so you can take a look at that.
Dr.
Yaszemski, Panel Members, thank you for allowing me to present this
morning. My name is Scott Tromanhauser,
I'm an orthopaedic spine surgeon at the New England Baptist Hospital in Boston,
Massachusetts.
I'm
a member of the Boston Spine Group, which is a six surgeon, two physiatrist
group who specialize in the treatment of adult degenerative disorders, and
adult spinal disorders in general.
Just
so you know who I am, I did my undergraduate work at the University of Buffalo
Medical School at Albany Medical College.
My residency at the Albany Medical Center Hospital, my spine surgery
fellowship at the New England Baptist Hospital, where I have been in practice
since 1992.
I
also performed a NASS Clinical Traveling Fellowship in 1996. I'm a clinical instructor in orthopaedic
surgery through Tufts University School of Medicine. My hospital is an associated orthopaedic surgery residency
teaching hospital for the New England Medical Center, which is a Tufts
affiliate, and the University of Massachusetts Medical School.
We
have six residents in orthopaedic surgery at our hospital, which is
predominantly an orthopaedic surgery hospital; 85 percent of the cases that we
do are orthopaedic surgery. And we have
three spine surgery fellows in our department. I'm also the chairman of the
Institutional Review Board at my hospital.
I
can speak about cages because I have a ten year experience with cages. I was a principal investigator at our
institution for the BAK cage, during its IDE days. I was a co-investigator for the RAY TFC cage, TIBFD cage from
Medtronic, the Novus-LT/BMP cage, and the -- presently the Cortek Polylok
cage. I also was a co-investigator for
the RAY Threaded Cervical Cage.
I
wanted to state that I support the FDA proposal for the reclassification of
interbody fusion devices for the following reasons. Why should I do that? We
may have skipped over a slide that I had, earlier.
My
disclosure is that OSMA paid my way here, and no other fee involved. I am a stockholder in Cortek, as a
co-founder.
The
reason I support this reclassification is that I can speak with ten years of
experience of primary and revision surgery involving fusion cages. I am very familiar with the risks of this
surgery, with the ways it can fail.
A
large portion of my practice is revision surgery. The Baptist is the unfortunate recipient of most of the revision
cases in New England. And I have to say
that many of the spinal implants that we use, on a regular basis, are already
classified as Class II, and carry essentially the same risks in their use, such
as pedicle screws and rods, spinal plates, whether placed ante or posterially,
and vertebral body replacement devices.
Which, by the way, probably carry greater risks than the use of
interbody fusion devices.
The
level of surgical skill required to use cages is similar to other Class II
spinal implants, and is commonly taught, at least in our training program at
the Baptist and, as well, in my residency training to the residents, and
certainly to the fellows.
I'd
like to make one point that I'm not sure is always clear to everyone. And that is the success of interbody fusion
cages can be defined in two ways, and this is the way I explain it to my
patients. There is technical
success, and there is clinical success.
Technical success means, did it fuse, was there any device related
adverse events. So that is really cage
performance. And I want my cages to
predictably create fusion.
Clinical
success, on the other hand, has nothing to do with the cage, unless the cage
fails itself. It has more to do with
patient selection. We all know that we
have sort of hit a ceiling with improvement and function, and pain, with most
fusion procedures. And it is because of
our limitations in patient selection.
And
in my experience probably 50 to 70 percent of the cases that I do I use some
sort of interbody fusion device, each one chosen specifically for the problem
at hand, whether there is deformity, osteoporosis, revision surgery, and what
the goals are of the surgery in general.
My
point of view on reclassification, and some of it reflects OSMA's position, as
I thought about this problem, and I had their input, I would ask that you don't
limit the use of supplemental fixation with cages. That is a decision we like to make, and I realize that your
mandate is not to tell us what to do, but it would be nice, from the surgeon's
point of view, to have the FDA support for what we do, on a regular basis.
We
would like to allow the use of allograft bone, and other bone graft substitute. And, Dr. Larntz, if I can address the
question you asked Mr. Zoletti, although we don't have any data to present to
you today about allograft bone, the archetype interbody fusion devices was
allograft bone.
Femoral
rings, for example, have a very long history of use in the spine, and continue
to be used, and have actually had a resurgence in the last number of
years. There is a long history of the
use of allograft bone in the spine.
Whether
you use allograft bone alone, whether it be inside a cage, there may not be a
lot of difference on how that performs.
I can't give you data, or point to specific studies, but if you would
require that, we can certainly provide it.
I
would also ask that the use not be limited to specific spinal levels. One of my partners, Dr. Frank Rand, does an
awful lot of deformity surgery that often involves the mid-thoracic and upper
lumbar spine, where cages become the best way to correct deformity, and he
might be working at T11, T12, L1, L2.
So
to limit their use, again, doesn't give us, as surgeons, any support from the
FDA on the use of these devices. I
would also not like to have any specific cage limited in surgical approach,
unless it is clear that it can't be used in any particular way, except from an
anterior approach, or except from a posterior approach.
Certainly
there are some cages that are too large to be implanted from the back so they
are, by necessity, implanted from the front.
But most cages that are used in the back can also be put in through the
front.
And,
again, I would agree with Mr. Zoletti that surgeons should be training
surgeons. I'm always, I think, disappointed by the experience I get from
companies with training sessions. And I
agree that they are not in the best position to decide who is trained to do a
procedure and who isn't.
And
there are certainly a lot of opportunities for surgeons who may be out of
training for some time, to get hands-on experience through the American Academy
of Orthopaedic Surgeons, through the North American Spine Society, through the
Neurosurgical Societies. There are
plenty of opportunities. So to require a company to do training doesn't seem
quite appropriate to us.
Thank
you. And if there are any questions,
perhaps some of those questions that were asked earlier, I might be able to
help you with. I don't recall them, but
--
CHAIR
YASZEMSKI: Thanks very much, Dr.
Tromanhauser. Questions for Dr.
Tromanhauser? Dr. Li.
DR.
LI: Yes, thank you for your
presentation. Can I ask you, in your practice,
in your institution, what percentage of your procedures are for revision of
these fusion devices?
DR.
TROMANHAUSER: These particular fusion
devices probably a small number. I
think most of the revision cases are done because someone hasn't used an
interbody fusion devices. And I will
explain that further.
Fusion
rates, in general, are not as good when a posterior procedure is done
alone. And some times if an anterior
procedure is done alone, it is not good enough for that particular situation,
either.
Most
of the revision procedures that I do are posterior infusions that have gone
wrong, in which case we are trying to increase our chances of fusion by adding
an anterior construct, a cage for example, in the intrabody space with bone, to
increase our fusion rate.
We
are also going to, of course, revise the posterior construct, whatever it may
have been. There are, certainly,
revisions of failed cages. Typically it
is a cage system that was used alone in the front, perhaps at multiple levels.
And
I agree with Tom Zdeblick, most of those failures are surgeon failures, if you
will, or technical difficulties; placed poorly, undersized, inappropriately
sized. And, again, that is a training
issue.
I
think your controls address that, and I hope I have answered your question.
DR.
LI: Did those device failures include
both metal and polymeric devices?
DR.
TROMANHAUSER: Few polymer devices
because there are fewer out there, in general.
But, yes, it involves both.
DR.
LI: And my last question for the
moment, is -- we have an interesting case where we have a device that depends
on fusion for success, yet there is no test for fusion prior to placing it into
a patient.
So
are you comfortable, as a surgeon, if the next company walks into your door
with a device that says, I don't know what it would be, but let's say it just
looks very different than a cage you are used to using.
Are
you satisfied that the currently existing tests, do you feel comfortable that
you would get fusion, or that it would survive the --
DR.
TROMANHAUSER: You mean the standards
for testing, of do you mean --
DR.
LI: Yes. With the currently existing guidelines and regulations, there is
no test for fusion, and there is no test for fracture. There is fatigue, but there is no test for
fracture.
So
someone comes in to you with a device that looks very different, made with a
material that you have no experience with, would you be comfortable saying,
because it has gone through these tests, that currently exist, that you would
be comfortable in using it in patients?
DR.
TROMANHAUSER: I guess the answer would
be yes. As a matter of fact, when a
sales representative comes to my door with a new device, the first thing I ask
them is, show me the biomechanical data, I want to see how this thing holds up,
how does it fail.
DR.
LI: Well, that is my point,
actually. There is no data that is
required of them to prevent fusion data, because I don't know how you would get
it. And there is no requirement to show
you any fracture data.
DR.
TROMANHAUSER: But there is --
DR.
LI: So the data they would give you
would be very complete with a couple of glaring exceptions.
DR.
TROMANHAUSER: Well, there is repetitive
--
DR.
LI: There is fatigue, but not fracture.
DR.
TROMANHAUSER: -- fatigue testing.
DR.
LI: Right, there is fatigue, but not
fracture.
DR.
TROMANHAUSER: Well, I guess if it meets
the fatigue testing standard, which most of these devices do, I would expect it
to perform adequately for fusion.
We
are looking for something that will hold up for six to twelve months. And in my experience the cages that we use
now, that has never been an issue. I
haven't seen a cage fracture, ever. I
have certainly seen them fail in other ways, but not because the cage itself
has failed mechanically, I guess, would be the best way to put that.
DR.
LI: I guess my question was inspired,
actually, by your key ring, where several of the polymeric constructs actually
have fractures and voids in them.
So
I would wonder that if you put those in a particular place, on a heavy person,
who picks up a 20 kilogram weight, you are putting 4,000 newtons of load on
this device that might be precracked or have voids in it.
DR.
TROMANHAUSER: There are broken devices
on my key ring?
DR.
LI: Yes, there are.
(Laughter.)
DR.
LI: There are.
DR.
TROMANHAUSER: Well, I don't know which
one it is, but --
DR.
LI: I will show you later, if you would
like.
DR.
TROMANHAUSER: I know there is one in
there that is a model, and it is not the real --
(Laughter.)
DR.
TROMANHAUSER: That has not been my
experience, that is all I can say. And
I have been at this for a while. I
haven't seen any broken cages.
CHAIR
YASZEMSKI: Thanks, Dr. Li. Dr. Naidu?
DR.
NAIDU: In fact your key ring inspired a
few of these questions that are coming up.
DR.
TROMANHAUSER: What did I bring that
for?
(Laughter.)
DR.
NAIDU: In your practice, in the last
ten years, have you used the plastic cages at all?
DR.
TROMANHAUSER: Yes.
DR.
NAIDU: What percentage would you say
that --
DR.
TROMANHAUSER: I use, what I think you
are referring to, is the DePuy Carbon Fiber PEEK cage. And there is also the Cortek Polylok, which
is under IDE now.
We
use the AcroMed interbody fusion device for posterior approach to fusion. I do it less often because I tend to be an
anterior surgeon. I think it is, in my
hands, a better operation.
Certainly
there are more people doing PLIFs, than doing ALIFs, posterior lumbar interbody
fusions, than doing anterior lumbar interbody fusions. My experience with that device is no
different than it is with metal cages.
I have not had one fail on me, except by non-union, for example.
DR.
NAIDU: But you've been using mostly
carbon fiber reinforced cages?
DR.
TROMANHAUSER: Mostly metal cages.
DR.
NAIDU: Mostly metal cages. And you occasionally use the carbon
reinforced PEEK. Now, on your key chain
I saw four plastic cages, one appears to be made purely of neat PEEK, and two
others do not seem to be reinforced as well.
I
see on reinforced, out of four. Do you
know how many of these pure polymeric neat matrix materials are floating around
just as cages, or are they all carbon fiber reinforced?
Because
the literature that we got, today, for this review, was mostly carbon fiber
reinforced cages. Do you know how many
of these are floating around, just plain old plastic, without any
reinforcement?
DR.
TROMANHAUSER: The only polymer cages, I
guess as I think about that, that I'm aware of are the Acromat interbody fusion
devices. And they also have a vertebral
body replacement, which I think they may be calling the intervertebral body
replacement.
I
forget what they call it, stackable cage is what it is called, and it is carbon
fiber PEEK device. Other than those
two, I'm not aware of any other, other than the large grey one you have in your
hand, that is the Cortek Polylok device that is not carbon fiber filled, and
that is under IDE right now.
DR.
NAIDU: So this is purely PEEK?
DR.
TROMANHAUSER: Pure PEEK.
CHAIR
YASZEMSKI: Thanks, Dr. Naidu. Any other questions for Dr.
Tromanhauser? Dr. Finnegan. Dr. Cheng?
DR.
CHENG: Thanks for your talk. I was wondering, I think there is an
important distinction to make during these talks today, to the FDA as well as
to the manufacturers, that there is a difference between stability providing
structural stability and fusion.
And
that is not always emphasized in the documents, or provided by the FDA and the
manufacturers. It is a point that was
brought out in Dr. Zdeblick's article, and I think it is important to realize.
So
I'm wondering, my question to you is, how do you asses, immediately
post-operatively, you provide stability.
But how do you asses whether or not you have provided fusion in the long
term? Is it just a failure, or the lack
of loosening over time? Or at what
point do you consider your patient to have a successful biological fusion?
DR.
TROMANHAUSER: Well, that is an
excellent question. It is an issue that
has come up before the FDA before. And
how do you assess fusion? Most of the
IDEs, the data, have included these bending films which, I would have to be
honest to say, we think are inadequate, but it is what the standard is.
I
can tell you, in my practice, the way I asses biofusion in every single case,
is with CT scan with reformatting images.
We have outstanding software, and an outstanding spine radiology team,
so we demand the best of them.
We
have twelve orthopaedic spine surgeons at my institution. And unless they do a good job, they are in
trouble. So I assess them with CT. There are ways of doing fusions to help you
make that assessment.
For
example, with a threaded cage, placed anteriorly, for example, you can go a
little bit shorter, leave enough room in the front of the cage to place a good
-- a bit of bone graft, so that you get what is called a sentinel fusion.
If
you see that solid sentinel fusion then you feel very good about it being
fused. You don't have to have it, in
order for it to be fused. And, in fact,
evaluating fusion status inside a cage is very difficult, even with the best of
CT scan software.
So
we assume, if someone is doing well, there are no loosencies around the cage,
that would indicate loosening, that it is fused. Even if we don't see sentinel fusion, and we can't tell it any
other way.
But
I think there are ways to make that determination, including the way you do the
surgery, and the way you image it.
DR.
CHENG: Would it be fair to say that
given the methods you have just described, I think most orthopaedic surgeons
have a good sense, in a long bone fracture, of when there is enough bony
ridging, or healing, biologically, that it will withstand the physiologic loads
of every day life.
But
in the spine that, perhaps, our ability to do that is not quite as good, even
with the sophisticated CT scanning you are mentioning, because a few spicules
of cancellous bone, seen through the holes in a cage, or elsewhere, as you are
suggesting, outside the cage, may not give you the same level of confidence as
the long bone fracture. Is that true?
DR.
TROMANHAUSER: Well, I can say that your
ability to image a long bone fracture is certainly a lot easier.
DR.
CHENG: Okay. I do have one second question and that is, you've mentioned some
rationale for reclassification. And I'm
just wondering, part of that was based on previous Class II implants, such as
the pedicle screws.
And
everyone in this room is familiar with the history of the Class Action lawsuit
that took place in the last years. And
I'm wondering, during the process of reclassification, what can we do, in terms
of your thoughts, in providing a process whereby we avoid something down the
road, such as what took place with the pedicle screws scenario?
In
other words, is there -- no one wants to see that debacle replayed, again, in
five years for cages as it has for the pedicle screws and other devices that
other of our colleagues, and other specialists have dealt with.
So
how can we prevent that from happening during our discussions today?
DR.
TROMANHAUSER: Well, that problem
started just as I was in training. My
recollection of it, correct me if I'm wrong, there were two issues. There were screws that broke, and there were
failures of fusion.
My
impression at the time was that there was a lot of confusion about the danger
of pedicle screws, because some people had a bad result. And there are always people who will not do
well with surgery of this nature, whether they are fused or not fused.
Certainly
if screws break they are not fused.
That is not, necessarily, a failure of -- it is a failure of the screw,
clearly, but it is more an indication that they didn't fuse. Then there is the whole patient selection
problem that I don't think you can address.
There
will always be people who don't do well, who will always raise these questions
of product deficiency when, in fact, it is not the product that failed, they
were not selected properly.
And
that is our biggest challenge, it is the next step that we need to take in this
field, it is trying to find a way to select patients more appropriately. Those people we can help we should try to
help. Those people that we clearly
can't help, we have to stop operating on.
And
we haven't gotten to a point where we can always predict who is who. The best way for you to address, I think,
that problem is to make sure the devices don't break, and then make sure that
they provide the stability that they should, that the testing is adequate.
And
beyond that I'm not sure there is much more you can do, because patient
selection is in the physician's hands.
CHAIR
YASZEMSKI: Thanks, Dr.
Tromanhauser. Dr. Finnegan, you had a
question?
DR.
FINNEGAN: Yes, I wanted to address
training. I, obviously, agree with you
that surgeons should train surgeons.
But, the fact of the matter is, you've been doing this a very long time,
but the spinal surgeon in mid-America hasn't been doing this for a long time.
Can
you give us some idea on how long do you think the average spinal surgeon, who
has not just come out of a fellowship, has been exposed to this? And what I'm thinking of is the transition
time.
I
mean, there is a group of people that need to get some really training to do
this, they are good spinal surgeons but haven't been exposed. So how long do you think your fellows, or
our department's fellows, or the Mayo fellows have been exposed to this?
DR.
TROMANHAUSER: I guess I'm not quite
understanding. How long will it take
for them to learn the procedure?
DR.
FINNEGAN: No. There are spinal surgeons who are about ready to retire who don't
want to know about this. There are the
fellows that you trained yesterday who know everything there is to know about
it.
And
then there are people in the middle who are not in academic centers, who are
doing good spine surgery, providing very good service, to mid-America, who have
not been exposed to this. And that is
the training I'm interested in, and how big do you think that group is?
Do
you think it is 50 percent of the spinal surgeons in the country?
DR.
TROMANHAUSER: I would tend not to think
so. I think that the -- most of the
people who are, this is pretty sophisticated spine surgery. I don't think you have general orthopaedic
surgeons in North Dakota doing spinal fusions of this nature, unless they've
had some training.
I
don't think it is the case that Dr. Smith in North Dakota saw this in a journal
and said, gee I saw that patient last week, calls the rep, has him come
in. I don't think that is happening.
The
exposure for an anterior approach is pretty specialized. We use a vascular surgeon in every single
case. Not every spine surgeon
does. So that is a pretty good obstacle
for them to do that.
So
what you are left with are people who are actively involved in the professional
societies, the North American Spine Society, the Neurosurgical Societies, the
Academy, who have the opportunity to see that sort of training every time they
go to a meeting, unless they don't go at all.
And
if someone is, I guess, that --
DR.
FINNEGAN: But they are not doing
hands-on, because hands-on is fairly expensive.
DR.
TROMANHAUSER: But the Academy does
hands-on workshops, and so does NASS.
DR.
FINNEGAN: And volume enough to cover
the people who don't -- because, with all due respect, actually one of our
residents is in South Dakota, is a spine surgeon, has been out for about 12
years, does extremely work, I'm sure does anteriors. But he is the type of person that I'm thinking about that, you
know, wouldn't have been exposed to, and trained and will be interested in
doing it.
DR.
TROMANHAUSER: But will also, probably,
take the time to go to those meetings, I would guess. I would hope so.
CHAIR
YASZEMSKI: Thank you. Dr. Naidu, you had another question?
DR.
NAIDU: Yes, a clinical question. You are the founder of Cortek, correct?
DR.
TROMANHAUSER: Co-founder.
DR.
NAIDU: Co-founder. Now, the implant that I saw was a neat PEEK
cage. It is a basic question, actually. Have you seen two neat PEEK parts wear
together, have you seen the particulate debris generated?
DR.
TROMANHAUSER: No.
DR.
NAIDU: Okay.
CHAIR
YASZEMSKI: Dr. Larntz?
DR.
LARNTZ: I'm intrigued, always intrigued
with sort of saying it doesn't work because we selected the patient
poorly. That is easy to say after the
fact.
What
I need to know is I need to know how hard people are working, and how many data
bases they are creating, and what they are really trying to do to get a real
decision analysis algorithm for patient selection.
I,
it seems to me that there probably are some predictive factors, or maybe we
will find out that there is an element of chance, in this world, which some of
us do believe in. Maybe we believe the
whole world is run by chance, actually, but that is a different story, and we
will go there later.
But
can you believe there really will be a patient selection algorithm that will be
effective? I heard what you said, it is
up to the individual surgeon to make that decision.
I
trust all surgeons, of course.
DR.
TROMANHAUSER: Why do I doubt that?
DR.
LARNTZ: But it would seem to me your
experience, if your experience is on 100 or 1,000 patients, there are how many,
200,000 of these implanted. Surely we
have data bases that are large enough to do at least some level of decision
analysis to take care of this patient selection problem.
It
is very nice, you know, when Dr. Zdeblick says at the end, patient selection is
the problem. It is very easy to say
that at the end. And that is easy to
say that is why they failed, because we didn't select them right, after the
fact.
But
I need to know, before you do the surgery, which patients to select. So is there an effort done, is there an
effort being made, sorry for this little spiel, for a decision analysis? A formal decision analysis.
DR.
TROMANHAUSER: Well, it is interesting
you should ask me that question, Dr. Larntz, because I spent the last five or
six years working on exactly that kind of problem.
I
just had a chapter published in a book called "Advances in Spinal
Fusion", I presented papers at the American Medical Informatics
Association, and at NASS, on predictive modeling for spinal fusion, using a
neural network-based predictive model.
And
what I tell my patients, this is the most difficult problem. I say, listen, I think you are a good
candidate. All the things that I have
available for me to choose you, and to evaluate you, tell me you fall into the
bucket that says you are a reasonable candidate. But I'm going to tell you, you could be one hundred percent
better, and think I'm God, you could be no better at all, and want to sue me,
but you may be solidly fused, either way.
And
there is something about these patients that we don't understand. Pain is a very complicated entity. And until we understand pain better we don't
even understand the mechanism of the production of pain from a degenerative
disc.
It
isn't instability per se, because as soon as I cut out the disc I know the pain
in general is going to be gone. My job,
then, is to fill the gap I made by taking out the disc. That is why we are here today.
And
until we can subdivide those patients into, by some indicator, whether it is
some kind of test, or some other psychological -- I mean, people have come up
with psychological testing, MMPIs, there is a lot of different ways.
And,
yes, there are some people whose profiles we know will fail every time. The 54 year old worker's compensation
patient who is 50 pounds overweight, smokes, narcotive addicted, has no family
support, may have a personality disorder, who knows, that guy is not going to
do so well.
You
come to me with back pain I assume you are an upstanding citizen. If you don't smoke cigarettes, and you are
healthy otherwise, I hope my government has chosen you appropriately.
(Laughter.)
DR.
LARNTZ: I'm just a statistician, not a
role model for anything else.
DR.
TROMANHAUSER: So we do make those
judgements. My role, as a physician, is
to try to help everybody I can, but not turn away anybody who could
benefit. So what we accept is a certain
failure rate to try to achieve that goal.
DR.
LARNTZ: And I understand that. But what
I think is very, very important, we don't often see these algorithms
distributed, and shown to people, and told.
And sometimes these papers don't always get published in the most
obvious places, and so on.
And
I think we do, you know, just a feature of light, we need to do more of this
formal decision analysis, and make it available. And recognize, sure, your chance -- and fusion is a different
issue, I think, than patient success, and that is --
DR.
TROMANHAUSER: That is exactly right,
that is the point I tried to make.
DR.
LARNTZ: I agree with previous panels we
have on that said we can always get a device that will fuse but do we know it
is going to help the patient is a different issue, and I think you made the
same point.
But
in fact I think that we don't do enough of using the real data we have to make
these decisions. And I think it is
going to be a multi-varied complex algorithm.
And I appreciate you using fairly sophisticated data in analytical, or
maybe we should call them data mining technologies which are very useful in
this area.
So
I advocate continuing to do that. Thank
you for your answer.
DR.
TROMANHAUSER: We may want to take that
conversation off line as a statistician.
It is very interesting work.
CHAIR
YASZEMSKI: Thank you so much. Other questions for Dr. Tromanhauser?
(No
response.)
CHAIR
YASZEMSKI: Thanks very much for your
presentation and discussion, Dr. Tromanhauser.
DR.
TROMANHAUSER: Thank you.
CHAIR
YASZEMSKI: We are now going to hear
representatives by Biorthex, Inc. We
have Dr. Benrabah and Mr. Leroux, in whatever order you would like to go. May I ask, sir, do each of you have a
presentation, or will one of you present?
DR.
LEROUX: My name is
Michel Leroux, I'm going to do the presentation, if I can find it somewhere.
CHAIR
YASZEMSKI: Thank you.
DR.
LEROUX: Again, my name is Michel
Leroux, I'm vice president of research and development of Biorthex
company. I have a PHD, I only have a
PHD in biomechanics, but I have some experience with interbody fusion cages,
and spinal surgeries.
I
think we cannot add much to the excellent previous presentations. And you can say that we agree with most of
the arguments. On the other hand, we
have a little short point we would like to stress today.
Just
to start, I will try to give you an overview of this presentation, just try to
present the company, our experience with IFDs, and our position relative to the
proposed statement.
We
are a very small company, we are a small spinal device developer and
manufacturer. Let's say that we are
more a research and development company.
So we don't have a lot of sales.
We are a quite young company, the company was founded in 1996.
We
have an office in Sioux Falls, South Dakota, and the French Canadian accent, is
coming from our head office based in Montreal.
As I said, we have a short experience with IFDs, so we have performed
500 surgeries, not 500,000, but 500 surgeries around the world, except in the
U.S.
We
already have two IDEs approved, and clinical trials are going to start very
soon. The results we have, actually,
are not that long, since this device has been introduced on the market less
than two years ago, so we have 1.5 to 2 years' results.
And
up to now we have very, very good results with the cage that I will present a
bit later, is different than what is actually in the U.S. market. So we have one reoperation, and it was not
device related.
I
think we had a high fusion rate, close to 97 percent. I would say that most cages implanted in Europe are done
stand-alone, without posterior
fixation. So I believe that even if
flexion/extension is not a standard foolproof, I believe that when there is no
anterior fixation, you have a good fusion rate.
We
have very good clinical outcome. Pain
and function improvement. We had, also,
good satisfaction from the surgeons.
And since we are not doing any posterior fixation, usually the patient
is going back home sooner, and back to normal activity, also, sooner.
I
didn't present any statistics, or anything.
But if you want to have a review of this data, they are referenced in
the document available at the entrance.
Now,
you know better Biorthex. We would like
to express, today, our support to the intervertebral body fusion
reclassification proposal. U.S.
patients and surgeons will benefit of a faster access to new products on the market.
I
think it is very important that, also, that if more U.S. surgeons are using new
devices, new and/or improved device, I think it will also reflect on other
surgeons and patients around the world.
So I think it is very important here to get American access and to get expertise from North
American surgeons to be able to reassure foreign surgeons and patients.
We
agree with the proposed CFR listing, maybe with the exception of the first
sentence in section 1, identification, where it states that the device made
from a variety of materials, including titanium alloys, and polymers.
We
strongly believe that to refer to generic materials does not support complete
safety and efficacy of the device made out of such material. That is why we have special controls in
everything.
On
the other hand we believe that it may have, the statement should, the
identification of materials may induce some bias in the evaluation of new
devices. As example, we can have new
titanium device that may not fit all the controls, and everything. So you have some kind of a bias that, okay,
submit a titanium we are going to approve this device.
On
the other hand we may have some device made of other material that may be
suitable for fusion cage, and it may have a more difficult access to a 510(k)
if it is made of another material than titanium or PEEK.
Actually
we are quite aware of at least one other material that presents the
requirements for such device, it is nitinol.
I think that this material fits all the recognized material standards,
we have the ASTM F-2062, and this standard identify underlie the specification
for wrought nickel titanium shape memory alloy for a medical device and
surgical implants.
I
think we have experience, also, in biocompatability, since we have a lot of
other device on the market made out of nitinol. We are talking of cardiac stents, or vascular stents for
different use, sutures, occluders, filters, bone anchors.
If
we look at Medline research on nitinol, you will see that there is close to 800
publications with close to 800 in 2003, just related to nitinol in medical
application.
We
believe that it is a sure material for medical applications. Let's say that nitinol is also available in
a porous form to permit tissue and growth and attachment. Biocompatability of the porous nitinol has
been assured through ISO 10993, Biological Evaluation of Medical Device, and
through adherence to existing material standards for nickel titanium alloy.
Porous
nickel-titanium, nickel titanium has been used in some countries for more than
15 years as an interbody fusion device, in different surgical procedures.
As
I said previously we recently introduced in Europe two of those device, one
lumbar, two lumbar sorry, and a cervical interbody fusion devices made of
porous nitinol in more than 500 patients which is not that bad.
Two
hundred patients were treated for lumbar disease, while 300 of those patients
were treated for cervical disease. The
result, collected through introductory trials, proved the device to be at least
as safe and effective than competitors on the market.
For
sure we are a small company, we don't have a lot of market, so we are able to
follow, very closely, the surgeons using our device. So we are very close to these patients.
So
being able to do this kind of follow-up is a good thing, because we really
realize that when this device is used mostly stand-alone procedure without
posterior fixation, and mostly without any bone graft, we have very good, very
good success with most of the users, right now, across the world.
We
also, with this device, porous nitinol device, we also meet all the mechanical
testing standards, compression, tension, torsion, expulsion, fatigue,
subsidence, animal testing, and everything.
It
reflect by the decision of the FDA to accept two of these IDEs for IFDs. Labeling is also an important part, and we
realize that we may have some concern relating to the nickel content of
nitinol.
On
the other hand we know that stainless
steel also has a large percentage of nickel in there. So we believe that special labeling, and keep the patient aware
and follow-up of this condition, will help to bring this device to the market,
and prove that it is safe and effective.
So
from our point of view there is some other material than titanium alloys and
polymer, that can be suitable to manufacture interbody fusion devices. We strongly believe that the general
reference to generic materials does not support the complete safety and
efficacy of the device, and that identification of only two materials imbues
some bias in the 510(k) evaluation of these new devices.
We
are, then, proposing or suggesting the following changes. The actual proposition we have in the
document, and we think that, probably, the most resolvable way is to just put
the interbody fusion devices made of a variety of materials that fulfill the
requirements of general and special controls.
I
think that you already discussed previously, are we going to have, let's say,
the guidance for titanium alloy, guidance for PEEK. I believe that the best solution is to have a single guidance to
cover all aspects, all materials, and not only titanium alloy, and PEEK.
And,
for sure, if everybody feels comfortable with new, other materials, we can try
to improve the list of these materials in the text, just to get the similar
access, or same chance to everybody to be accept through a 510(k). Thank you.
CHAIR
YASZEMSKI: Thanks very much, Dr.
Leroux. Also my apologies, you were not
listed as Dr. Leroux for your --
DR.
LEROUX: That is okay.
CHAIR
YASZEMSKI: -- incorrect introduction of
you before. Do we have questions from
the Panel for Dr. Leroux?
(No
response.)
CHAIR
YASZEMSKI: Seeing none, thank you for
your time.
We
are going to move on now, if we can, and shift gears just a little bit, to the
open public hearing portion. And prior
to doing this, we will state that we received no requests for anyone to speak
at the open public hearing, but that opportunity exists for anyone who would
like to.
So
I will ask now, is there anyone present who would like to address the Panel at
this time? If you would like to do so,
please identify yourself and come forward.
(No
response.)
CHAIR
YASZEMSKI: Seeing nobody we will do the
following. The next portion of the
meeting is going to be the Panel deliberations. But I'm going to recommend that we take a short break now, a ten
minute break, and give everybody an opportunity to stretch, and use the rest
room if they need to.
It
is now 20 minutes to 11. If possible I
would like to ask everyone to come back and be seated at 10 to 11, and at that
time we are going to ask Dr. Diaz to move forward with his presentation. So we are adjourned for ten minutes.
(Whereupon, the
above-entitled matter went off the record at 10:42 a.m. and went back on the record at 10:52 a.m.)
CHAIR
YASZEMSKI: Welcome back,
everybody. I would like to call the
meeting back to order and remind the public, again, that while this meeting is
open for public observation, public attendees may not participate, except at
the specific request of the Panel.
We
will now begin the Panel discussion. A
deputized voting member of this panel will open this part of the meeting with
remarks. Dr. Fernando
Diaz will give his remarks on the proposed reclassification.
After
that the Panel will have a general discussion, after which the Panel will focus
their deliberations on the FDA questions.
Then Ms. Shulman will guide the completion of the reclassification
questionnaire, and supplemental data sheet forms.
Finally
the Panel will conclude their deliberations by voting on the completed forms,
and setting out their recommendation to the FDA.
The
Panel can ask the sponsor, or FDA, questions at any time. Prior to Dr. Diaz' presentation, I would
like to ask for comments from Dr.
Witten. Dr. Witten?
DR.
WITTEN: Yes, thanks. I just want to clarify what we think we are
doing or, at least, what FDA thinks it is doing with this reclassification, in
light of some of the comments made by the three industry presenters, which we
certainly appreciated hearing.
And
these comments relate to what was said about the use of supplemental internal
fixation, the use with allograft bone and other approved bone substitutes; the
spinal levels, and the use of other materials for cages.
So
let me just say that, and perhaps it should have been part of the device
description. But our proposal is to
reclassify all of the device, the existing PMA devices, other than the one that
uses BMP.
And
so one of those devices is with additional internal fixation, so the intent was
to also reclassify that device. And
that may mean that the language needs to also say with and without supplemental
internal fixation.
Since
that is our intention, that is the intention of the proposal. And so perhaps that language needs to be
added.
As
far as some of the other things, the use with allograft bone, and the spinal
levels, and the other materials, I will just make the following generic
comments, which is that we can only reclassify what we've actually seen. That is what we have actually approved.
So
the reclassification would be for, you know, the existing products. And then what would happen, if a sponsor
came in with something different, a different material, or a different level,
or to be used with a different something other than allograft, is we would
evaluate that through the substantial equivalence process, and see whether or
not the product with data, or without, with whatever the sponsor provided, was
able to demonstrate substantial equivalence to the products that we had already
cleared.
And
so based on that substantial, the review process, we might decide that we need
some types of additional information, or not, and could include, you know, anything
could include bench testing, animal testing, potentially clinical data.
So
that would be part of the review process.
So, in other words, in our minds this would leave it open to have these
different types of devices, but we would need a demonstration of substantial
equivalence in order to make that determination.
So
when you are talking, I think that clarifies at least what we think we are
doing with the proposal. In your discussions, if you have any specific
comments about what kinds of information, or what kinds of testing, that you
think we might want to think about, or whether you think that there is, you
know, some specific concerns that you would like to highlight about this
approach, either one, please we welcome those comments as well.
CHAIR
YASZEMSKI: All right. Thanks very much, Dr. Witten. Dr. Diaz?
DR.
DIAZ: Yes. I've been asked to give a presentation from
the Panel perspective on what these devices mean and what, based on the
literature available to us, and my personal experience, these devices can be
viewed from the perspective of changing classification.
I
would like to view it from the perspective of safety and efficacy, as opposed
to what you heard earlier, start with indications and with patient selection.
I
realize that that is not what we are here to see but that is, very often, the
critical aspect of what we do. Spine
surgeons are required to make very specific decisions in the choice of
instrumentation they use, based on the indication for the right patient, for
the right tool, to provide the appropriate outcome.
Patient
selection is, without a doubt, the most critical part in this process. We may have the best tool in the market, if
that tool is used for the wrong person, the tool will fail.
If
the patient has comorbidities that will not allow for the patient's use of that
particular device to be successful, the device will fail through no fault of
the device itself, through no fault of the surgeon, him or herself, but through
the fault of the comorbidity selection of that patient.
A
patient who is a smoker, a patient who has additional diabetes, hypertension,
or cancer; a person who has a work compensation history of pain and disability
will likely not be successful, or as successful as the right person for the
right indication, with the right tool.
In
regard to the cages themselves as you heard this morning, the cages come in a
variety of flavors, colors, shapes and sizes.
The best description are those which are metal, those which are
non-metal, mostly PEEK supported by carbon fiber, or some other coating
material.
The
shape can be square, or box in nature.
They can be cylindrical with or without threads. The approach can be anterior or posterior,
depending on the patient habitus, depending on the patient's risk status,
depending on the selection by the surgeon.
The
approach in the application of the device makes a difference on failure of the
device. Again, not predicated on the
device itself, but on the application used by the surgeon in choosing one
approach versus the other.
Success
we measure by two criteria, one is clinical criteria, the other one is
mechanical criteria. The one that we
want to look at the most is the clinical success rate, is the patient's pain
and neurological problem resolved.
If
that is the case, very often, the device in and of itself, and what it does,
will not make a whole hell of a lot of difference to any of us. We will be satisfied with the outcome
because the patient is doing better.
The
reverse is more common, where we have a patient that has an outstanding
mechanical success, with a fusion that is as solid as a rock, but the patient
continues to complain of pain, or neurological dysfunction.
What
we are being asked to do is, really, to reclassify a set of devices that are
very comparable to a set of devices that are already classified at a different
level. Vertebral body replacement
devices are almost identical in shape, size, form, and application to what the
intervertebral body devices do.
There
is very little difference in those two set of applications in the type of
instrumentation we use; the approach in which they are used, the application
for which they are used, and the success rate that they will provide.
What
I would like to leave you with, as a conclusion, is that the device, in and of
itself, may not answer all the things that we want to answer today. The success rate, be it clinical or
mechanical, may or may not be predicated entirely on the device itself, but on
the patient selection, in that there is a group of devices that we have already
approved, as a level II set of devices that are nearly identical to those we
are using for intervertebral disc replacement.
Thank you.
CHAIR
YASZEMSKI: Thanks very much, Dr.
Diaz. We are going to proceed now to a
general discussion. What we will do, in
this general discussion, is ask the Panel members to speak to
any of the presentations that have been given, call back any of the presenters
to the podium, to ask them specific questions or, in general, to comment on the
issues before us.
Once
we feel that we've had an adequate discussion of a general nature we are going
to move to a specific discussion of each of the five questions that the FDA is
asking us to consider today.
When
we move to that portion of the discussion, if I can, I'll ask Ms. Anderson to
project the questions, one at a time, and we will go around to each panel
member, and ask each panel member, to make a comment on each question.
Let's
open the general discussion now. Panel
members? Dr. Finnegan.
DR.
FINNEGAN: I have a question now for Dr.
Witten, although this may not be the person I should ask.
One
of the things, besides supplemental fixation, people have talked about is
surgical approach. Are you considering, also, in the guidance documents opening
that up, or may I ask how you plan to approach that?
Or
perhaps a more generic question, do most Class II have limited surgical
approaches per their guidance documents?
DR.
WITTEN: Well, I think our thinking was
to, you know, to reclassify the devices generically and then have the specific
instructions, the sponsor can have specific instructions, and we would look at
those and see whether or not that device, with those instructions for use, was
substantially equivalent to what was on the market.
I
mean, there is products, some of the products approved right now are approved
with -- there are different approaches represented by the products group right
now, currently.
DR.
FINNEGAN: Then I guess my next question
would be can all of these products be used with all of the approaches?
DR.
WITTEN: Maybe I didn't answer clearly,
then. So can I try again? So in a product, you know, when we clear a
product it has to have the product and instructions for use for that product.
So
it doesn't necessarily mean that any product would get generic instructions for
use, of use anyway you can. The sponsor
would need to propose instructions, the product and the instructions, and we
would look at that.
DR.
FINNEGAN: I hate to be a real pain in
the derriere, but I'm going to be one.
You, what is the word I want, you put as a Class II IM femoral
rods. And am I assuming that you put
them to go from the hip towards the knee, and so then when some of us decided
to put them from the knee towards the hip, we were violating the guidance
document?
DR.
DIAZ: Maybe I can answer that. There are some of these products that can be
used either from the anterior or the posterior approach. Not all of them, uniformly, can be used that
way.
But
there is a distinct group of them that can.
The quality, the safety, and the efficacy, does not really change much
in those products, depending on the approach.
There are some that have very unique specific applications for the
anterior approach.
The
prime example is the LT-Cage that is a conical cage, that can only be placed
through the front. And so with that
caveat the approach does not really matter a lot for the majority of them.
DR.
FINNEGAN: And that was my concern. My concern is when you do a PMA you want to
put in the safest way possible so that you can get the best results. But when it goes into the real world if, in
fact, it can be as a surgeon feels comfortable and, perhaps, the situation
dictates, then I would be concerned that it not be limited by the PMA
instructions.
DR.
DIAZ: Yes. The safety there is really predicated in the surgeon's
experience, the patient's habitus, the accessibility to the approach, and the
location of the problem.
CHAIR
YASZEMSKI: Thank you, Dr. Finnegan, and
Dr. Diaz. Other questions,
comments? Dr. Naidu.
DR.
NAIDU: You know, it seems as if we are
discussing two different issues here.
One is clinical results, which Dr. Diaz explicitly stated, and it is
based mostly on patient selection, rather than the device itself.
And
if the patient does well it doesn't matter what the device is, and we have a
great outcome. But I'm not so sure it
is that simple. I mean, materially, you
have two different materials here. You
have metallic and you have polymeric.
The
polymeric materials, even though you've defined the matrix as PEEK, you can
vary that in many ways. And, for
example, one of the products in the key chain that was presented was a pure
knee PEEK. It can be reinforced, and
those are -- I mean, I think material importance is also a key issue here.
You
can't dismiss that because if those plastic devices fracture, in vivo, and neat
PEEK is, essentially, a soft material.
If it wears, PEEK on PEEK wear produces terrible debris.
I'm not so sure that we have enough
special controls. My concern is that
I'm not so sure that we have enough special controls to classify polymeric
materials, and metallic materials under one single guidance, that is my
concern.
I'm
not so sure that the tests that are mentioned so far here really fulfill all
the criteria for one guidance document.
It may be that we need to split these devices into a metallic, pure
metallic component, and polymeric components, and write two separate guidance
documents.
I
mean, I think there are two issues here.
Because the polymeric materials are not equal to metallic, no matter
what you say. I mean, it may be that
patient's outcome is important but, nevertheless, in extreme cases where the
polymeric materials fail, the results can be devastating.
You
know, polymeric wear debris is, especially PEEK wear debris is terrible. I mean, I'm going to ask Dr. Li to comment
on that further. Do you have any --
CHAIR
YASZEMSKI: Dr. Li?
DR.
LI: I happen to have a comment on
that. Actually I have a page of
comments on that. I completely agree
with you. I also agree that the
polymeric and metallic devices should be considered separately.
We
have a couple of issues here. The few
clinical results that we've gotten here seem to indicate that the devices is
safe and efficacious. And the reports
are very few of an actual device failure.
However,
I will say that the MDR is a particularly bad place to use that data set to
convince yourself that, in fact, fracture doesn't occur, and what level it
occurs, or doesn't occur. It is
something on the order of a tenth of a percent in this case.
So
I go out for two things. Either that
they, in fact, don't break which would be good, but then it would just be plain
fortunate, because there is no test, for instance, for fracture. And the loads that I've seen are way under
what they should be, for instance, for a 200 pound person picking up a ten
pound weight.
The
loads being applied to these devices are about one quarter the loads that you
would see. So I'm unconvinced that the
materials testing, for the polymer side, especially, is sufficient.
Specifically
they call out PEEK, and they give us a PEEK guidance document. But that PEEK guidance document is,
specifically, for neat PEEK. There is
no guidance document for reinforced anything, in this device, including PEEK.
So,
and even if there was, don't underestimate the ability of the bioengineer to
screw up a good product by changing something small, like the length of the fiber,
the type of the fiber, orientation, molecular weight of the polymer, the list
goes on forever, for the ways that I could screw this up.
So
it could be that they are not breaking, but it could be just a fortunate
happenstance that these particular groups don't break. But, for instance, if you make it a Class II
it would be, if you change it from PEEK to PEK, or you use -- there is
resorbable ones, there is a whole host of polymers that could find their way into
it.
I
don't believe that the existing tests would guarantee that they, in fact, will
not fail. And, actually, that kind of
separates also into the cervical placements, and the lumbar placements.
The
cervical loads are, in fact, very low under any condition. But because the -- because body weight
actually plays a big part in the lumbar loads, the lumbar loads are
substantially higher, maybe ten times higher.
So
I think that it is a little bit dangerous, on the polymeric side, if you have
something surviving in a cervical application, that you would guarantee that it
would survive in a lumbar application.
It
might, but if it does, at the moment, we are just lucky. And the other thing that I'm uncomfortable
with, a little bit, is that although these are fusion devices, there is no test
for fusion.
So
if someone comes in with a different material, a different structure, a
different geometry, it seems so far that everything that has been tried has
fused. But, again, don't underestimate
the ability for us to come up with something that, in fact, won't fuse. Because, in fact, we have no way to pretest
that.
And
the only way we are going to find out now is when the surgeon puts them in and
all of a sudden finds a very low fusion rate.
And
I have a question for Dr. Larntz, now that I get off my soap box. In looking at the data that we presented,
are you convinced, in fact, that all these devices are equivalent to each
other?
CHAIR
YASZEMSKI: Dr. Larntz, go ahead.
DR.
LARNTZ: Wow, that is -- am I convinced
that they are equivalent to each other?
Well, of course, they are not equivalent to each other. But that is not, you know, statistically
equivalent, I think -- I have done no analysis to answer your question.
And
I can't imagine that they are actually exactly equivalent. But I don't think that is a requirement that
we have here, okay? I think there is
going to be a range of performance.
I
looked at these shapes and I'm not, you know, I don't know anything about this,
but they sure seem different in the shape.
They sure seem different in all kinds of characteristics which all of
you engineers can do all the testing.
I
do have a comment, I'm going to make a comment later about testing. But I think that all these devices have, I
mean, is it seven that have been passed?
I can't remember now, it is six or seven, anyway, that have been passed.
And
there is six that are like the ones that we are asked to reclassify. If you look at the data that they have, they
are all effective devices, with respect to what they are aiming at. They are all -- if you read the papers, I
mean, they are pretty -- I realize that I made a big deal of patient selection,
because there is always going to be patient variability.
But
these devices that we are asked to be reclassified, statistically, I haven't
seen a great deal of difference across them.
How is that? Nothing
obvious.
But,
you know, if someone comes in with a very low fusion rate, but the device may,
in fact, work clinically for all I know, right? I mean, we have been in this panel before where people say, well
it is supposed to do just what it is supposed to do. If it is supposed to be a fusion device we are going to count it,
and that is good.
But
we don't know if that is going to translate to clinical success. I would rather
have a device that I don't care if it fuses, I'd rather have a device that has
clinical success. And I think that is
very hard to predict, besides patient selection.
So
sorry to go around your question but I think -- I don't think that we have any
strong evidence that this group of devices that we see here are very, very
different, with respect to performance. And
I do agree that patient selection, patient mix is a big part of performance.
CHAIR
YASZEMSKI: Thanks, Dr. Larntz. Mr. Melkerson, do you have a comment?
MR.
MELKERSON: I'm Mark Melkerson, Deputy
Director for the Reviewing Division and some clarification and some examples.
In
terms of polymeric materials, we would consider each change to the polymer a
new material. And to address those
types of things it could be something as simple as animal testing, to clinical
data.
And
the example I would bring forth would be what was done for bone fixation
appliances made out of resorbable polymers of various types, found equivalent
to metallic implants.
Initially
that was required, they had to have clinical data to demonstrate that they were
equivalent in clinical success to a metallic plate for the same indications for
use.
Later
that information was backed down after we had gained experiences with families
of polymers, backed down to just requiring animal data. So under the 510(k) process we are allowed
to ask for clinical data for those things that are, indeed, different.
And
they as we gain experience with families, or particular polymers, back down
those requirements to animal studies, or just bench top testing.
CHAIR
YASZEMSKI: Thanks very much, Mr.
Melkerson. Dr. Cheng?
DR.
CHENG: Just a question for Steve. I thought I heard you say that there are no
tests for failure of these devices, did I hear you say that?
DR.
LI: There is no test for fracture. They have a fatigue test, but fatigue and
fracture are really not the same thing.
The fatigue test is actually very dependent upon the geometry and method
of loading, and the amount of load that you apply.
It
is not really a basic material property.
So different things, for instance, can have a very high fatigue
strength, but a very low fracture rate.
So the issue here is that they are two different properties.
And
I would worry, especially in the early stages where fusion hasn't occurred, and
the device is basically left to stand on its own, to support whatever load it
is going to see, that -- again, I'm not really talking about the current
devices, I'm really worried about could be coming on down the line.
That
you could have a device that would survive a fatigue test at the time they
proposed but would, in fact, fail a fracture test.
CHAIR
YASZEMSKI: Dr. Li, may I ask you for a
clarification? The tests that you speak
of were not in the material that was presented to us, but these tests could be
done, is that correct? They could be
specified, a fracture test could be asked for?
DR.
LI: Yes, they could be. But they are
currently absent in any of the documents that we have gotten so far.
DR.
CHENG: Maybe I'm misunderstanding
something. But I'm reviewing the
guidance documents, in the back of our packet, and it seems to me that static
testing is, in addition to fatigue testing, static testing to structural
failure is required.
DR.
LI: Again, that is not a fracture
test. In other words, is the difference
for me applying a test to bend this pen, as opposed to breaking.
All
the static tests are, basically, low speed, very slow test design to get a material
failure point. It would be the
difference between breaking a stick and then pulling a stick so much that it
breaks that way.
So,
in other words, fracture is a specific failure mode that is not addressed in
any of the tests that we've got. This is
not bad mouthing any of the existing tests.
It just doesn't address the issue of fracture should they change the
material geometry, or the percent of filler, or whatever.
DR.
LARNTZ: Could I ask a question --
DR.
CHENG: One second, if I could continue? The reason is because the FDA hasn't
requested that, or the reason is because the test doesn't exist?
DR.
LI: No, the test exists. Let me give you an example. For instance, the highly cross linked
polyethylene that is used in acetabular components now passes all the fatigue
tests, but yet has a fracture strength of one/one hundredth of that, of the
none highly cross linked poly.
In
other words, so it is unlikely that you are going to break a highly cross
linked cup by repetitive loading but it is possible, it is one hundred times
more likely, that if there is a pre-notch in the wrong place, loaded at a
certain time, that the cup will actually break.
So
fatigue and fracture are not the same thing.
And the tests exist for fracture, they are just currently not called out
in this particular device. And, again,
I'm more worried about the polymeric structures than I am the metal structures.
DR.
CHENG: I see, okay. I have a separate issue I will take up
later.
CHAIR
YASZEMSKI: Dr. Larntz?
DR.
LARNTZ: I just want to clarify. I think I might be a little lost. We have no guidance document for this set,
right? We have an example of a guidance
document in the back for other devices, but am I right that you are going to
develop a guidance document if this goes to Class II, is that --
DR.
WITTEN: That is right, the guidance
documents which were provided are to give you an idea of the kind of
information that is in a guidance document.
And also -- well, there is two, there is one on clinical studies, and
there is one on 510(k)s for the other devices.
So
I think it gives a fair idea of the kinds of things that --
DR.
LARNTZ: Right. But if we want to ask for a particular test,
if we want to suggest those, and put those -- then that is --
DR.
WITTEN: Well, that actually is part of
our questions, which is, if you've identified the risks, can you identify
special controls.
DR.
LARNTZ: Okay, I just wanted to make
sure.
DR.
LI: I will say that it is not in their
PMA either. The fracture testing is
also not in the existing PMA requests and documents. We can add them on, but that is the basis for which I was making
my comments.
DR.
LARNTZ: But these devices that have
been approved, and this panel has approved, and I sat here once or twice and
approved something, and I actually stood over there once or twice, and we've
approved something too.
I
think these devices are working. I
mean, we are not questioning the devices now, I don't think. We are questioning whether or not they can
be down classified, if the Agency has enough information to go to Class II, and
if we can specify and help the Agency in laying out how they should ask for
tests.
If
a fracture test seems to be important I'd hate to think, and I'm not sure if
our industry rep might comment on this, that we are going to ask all these
already approved devices to go back and do fracture testing? I don't think we are going to do that.
DR.
LI: No, well --
DR.
LARNTZ: Nor do I think of a new
one -- well, okay.
MS.
MAHER: Can I add something?
CHAIR
YASZEMSKI: Ms. Maher, go ahead.
MS.
MAHER: I'm Sally Maher, the industry
rep. I think Dr. Li, you are implying
that these things won't go through a thorough review if they are 510(k) for a
new material. And that, in fact, isn't
true.
There
will be a guidance document developed, it will be a very thorough review. And if there is a new material the FDA and
the sponsor would work together to develop a test that appears to be the most
appropriate for it.
And
I think we have discussed a lot -- I've heard a lot of discussion about the
PEEK versus the metal. You've never
requested the fracture test for the cages that are currently on the market. We haven't seen it as an issue yet, for the
cages that are currently on the market.
And
maybe if Mr. Christianson, who works for a company that makes one of the PEEK
products, would want to talk a little bit about the testing t they do do on
their products, it may alleviate some of the concerns.
DR.
LI: Again, can I clarify a little
bit? I'm not disparaging, in any way,
the products that we have in front of us at the moment. And I'm even willing to believe,
optimistically, that fractures are rare.
But
let me point out two things. One, we
don't really know what the failure rate is because the only thing we are going
by is the MDR reports, and a couple of clinical studies done by the
investigators who are proponents of the device.
So
I would say, first of all, we don't exactly know what the fracture rate
is. And certainly, unfortunately you
showed the key chain, that some of those devices on the key chain are
fractured.
And
if you would put those into a 200 pound guy, picking up a 10 pound weight I
would be surprised, in fact, if that device didn't crack all the way through.
So
the fact that we don't have any, I think, is good. But I'm worried that that is just because we have been
lucky. And so as we go on down the
line, and we down classify, I just want to be sure that these controls are in
place so that when you change structure, and change materials, or change
whatever, that those tests exist.
In
fact I would recommend, in fact, if you take the optimistic view that, in fact,
fracture doesn't occur currently, that you measure the fracture toughness of the
current devices, and all future devices have to be that fracture toughness or
more.
So
I would go back and recommend that you, in fact, do the fracture toughness
testing on the existing devices but use that, essentially, as a guideline for
at least the minimum fracture toughness of all future devices.
MS.
MAHER: I would actually suggest we not
use the key chain as an example, since it has been knocking around in a car,
and a briefcase, for God knows how long, it is not a sterile --
DR.
LI: Well, let me just say that those
devices are not unusual for polymeric composite devices.
CHAIR
YASZEMSKI: Thank you. I think if I can summarize this discussion,
when we have issues like these we will be able to communicate them to FDA as
concerns, and they can be incorporated in the FDA's assessment of what special
controls are needed.
So
this is good, and we do have a method in place to include them. I would like to ask one more thing, if I
might, and I will get to Dr. Cheng.
I
want to give an opportunity for our patient representative to speak if she
would like to. Ms. Wells, is there
anything you would like to add?
MS.
WELLS: Not at this point. The thing that is a bit confusing to me is
the fact that these devices have been around in another format. In other words, as a spinal replacement in
Class II.
So
I know the concern is here, as far as the polymers are concerned. But I think with the guidance documents we
are going to be okay with looking at the different polymers versus the metal.
CHAIR
YASZEMSKI: Thank you very much. Dr. Cheng?
DR.
CHENG: I have a concern that I don't
know if it is addressed in the questions to us, so I just wanted to bring it
up.
If
I were a patient about to undergo placement of one of these devices for arthrosis
of my spine I think the long term complication that I would be worried about
most would be adjacent segment disease.
And
I know a number of factors that determine your risk for that depend on anatomic
location, and how many segments are fused.
But the question I might ask the spine surgeons on this panel, and
perhaps in the audience, is there -- does the type of device implanted, or
perhaps I should say the rigidity of the device implanted, play a role in
determining the risk for subsequent adjacent segment disease in the long term?
DR.
DIAZ: Maybe I can answer that. The
problem that arises with the implantation of an intervertebral device, and the
acquisition of a fusion, is that you basically immobilize a segment. So you take that segment out of the
biomechanical
activity of the spine.
When
you do that you increase the load above and below, like Dr. Li was saying, by a
series of newtons. And so the
mechanical work becomes greater for that segment, and there is no difference
between the structure of the device being metal, or being plastic or PEEK.
The
ultimate result will be fusion in both.
And if that is what happens the common denominator will be increased
load at the level above and below. So
the device itself plays very little to no role in the ultimate development of
additional disease.
DR.
CHENG: I guess I was wondering if the
modulus of elasticity is different enough that the stress, or the number of
newtons, apply to the adjacent segment may change, as is the case for implants
in other areas of the body.
DR.
DIAZ: The reality of the difference in
the modulus of elasticity is that the probability for fusion is increased with
the PEEK type device, because it is more of a load -- it is not load bearing
like the metal cage is, it is more load sharing.
So
the probability for fusion is heightened with a plastic, or a PEEK device,
versus a metal device. Ultimately,
though, if at the end of the nine months, as was mentioned earlier, if the
spine is fused, the end result is no different.
CHAIR
YASZEMSKI: Thanks, Dr. Diaz. Dr. Finnegan?
DR.
FINNEGAN: I'd like to address the
concern about metal versus polymer. In
the literature that we were given the polymer studies all had posterior
instrumentation with the polymers.
Do
we know of any polymers that are used without posterior instrumentation? Because that is a totally different dynamic.
DR.
DIAZ: The experience in the literature
has been that when you use a posterior approach, almost uniformly, irrespective
of the kind of material you use, be it metal or be it polymer, the likelihood
of success is considerably less than if you use the device with the additional
of internal instrumentations, spinal fixation.
The
reason for that is because you destroy the facets on both sides, and you create
an unstable spine. So the addition of
devices is just to prevent mobility.
DR.
FINNEGAN: Yes, because you go through
three columns. But my concern, more, is
has anyone done an anterior approach with the polymers, without posterior fixation?
DR.
DIAZ: In fact some of the newer devices
are used that way. And there is a couple of papers here that are showing
encouraging results using just the pure anterior approach. I believe one of these is, I can't remember
exactly which one it is.
Maybe
I am thinking of the metal one that just promotes the use of purely the
anterior approach, the BAK. But the
tendency, in general, is that if you disturb little the other two columns, the
probability for success, if you use the ideal structure, is going to be
greater.
DR.
FINNEGAN: But my concern, and I agree
with what has been said before, is that the load on the polymer is
significantly different if you go anterior and it is taking all of the load, as
compared to if you do a combined anterior posterior.
DR.
DIAZ: But when you put the device alone
here, the elasticity of the material itself, from my experience, has been such
that fracture has not been a problem, fusion has occurred in the vast majority
of cases.
And
I think that is what the literature bears.
I understand the concerns for the fracture and the load stress on the
material. But I don't think that has
been a problem. I would like to hear
what others have experienced.
CHAIR
YASZEMSKI: May I make a
suggestion? I've noticed that the
discussion items have been, now, sort of going into areas that have been asked
in specific questions by the FDA, but we are going back and forth among a few
of them.
And
it may be time, if no one has any objections, to move to the FDA questions, and
we will continue with the same discussions, but in the format of one question
at a time.
DR.
LARNTZ: Can I make my one final
comment?
CHAIR
YASZEMSKI: Dr. Larntz, go ahead, while
Ms. Anderson is getting her slides up.
DR.
LARNTZ: I said I would like to make one
comment. And I noticed that you rely on
ASTM testing, and standards. And let me
remind us that they are not all perfect, and that often the FDA should require
more testing than is indicated in these documents.
For
instance, in the F-136 document to pass a material you have to test two
samples. Two. You've got that? If they
both pass, material passes. If one
fails, though, in typical -- I didn't say that, I was going to say in typical
engineering fashion, I didn't say that.
But
if one fails, actually it doesn't say if one or more fails then, in fact, what
you can do is test two more. If they
pass it passes. Now, I just did a
simple calculation because I didn't have too much to do.
And
I said, what if this material has a failure rate of 50 percent, what if it
does? Just, for instance, to pick a
number out of the air, which I don't consider very good, you know, 50 percent
failure rate.
This
testing procedure advocated by ASTM would only pass 32.5 percent of the
materials. Do you hear me? Even at a 50 percent failure rate the
testing procedure, we would catch actually 67 percent. Is that good? It is not good enough as far as I'm concerned.
So
let's be very careful in just saying we are going to use an ASTM procedure, make
sure -- and I know that you have good statisticians who can help you with
sample sizes, and so on, so that you have actually good evidence.
And
I know that you would do that. But I
just want to make sure we just don't say we are going to use an ASTM standard,
especially ASTM standards that advocate such rotten statistics.
CHAIR
YASZEMSKI: Go ahead, Dr. Li.
DR.
LI: I'm not quite sure where else to
put this comment. Not to beat a dead
horse but the one difference, another difference between the polymeric and
metal constructs is that I think the polymeric materials, especially the
composite ones, are going to be much more notch-sensitive than a metal.
If
you put a nick into a relatively thick piece of titanium not much, probably, is
going to happen. But if you put a nick
into a composite, typically you reduce both the fatigue and fracture life by
orders of magnitude.
And,
in fact, in one of the publications we've got here, two of the devices out of
74 were broken interoperatively out insertion. Fortunately they noticed.
So
that is another thing that is different about the polymeric, and the metal
device. The metal device is,
essentially, more surgeon proof, if you will, especially if you are going to
have additional affixation appliances around that device.
CHAIR
YASZEMSKI: Thanks, Dr. Li. Well, we are going to do the specific
questions. I would like to ask every
panel member, individually, to make a comment on the question. And if you have nothing to add to that
question, please just say so, and we will move on to the next person.
We
are going to go clockwise and start with a different person each time. And so for the first question I'm going to
start with Dr. Naidu, and the next question Dr. Larntz, and the third question
Ms. Wells, and then we'll move along around and everybody will get a chance to
speak.
The
first question is to please discuss the descriptive information and intended
use presented in the reclassification identification.
MS.
ANDERSON: For your ease I'm just putting
up the device description. And if you
want to break this question into two, look at the device description first, and
then I can switch slides.
CHAIR
YASZEMSKI: That will be fine, a little
easier to do. And let's give Dr. Naidu
a moment to look at the device description and then ask him for comments, and
then move on to Dr. Larntz.
DR.
NAIDU: I have several issues that I
would like to bring up to the attention of the Panel. I think we are talking about two different devices here.
That
has been my opinion after looking at all the clinical data, as well, because
all the papers that we have been presented to date, numerous results on
metallic cages are available.
However,
there is paucity of data with regards to polymeric devices. Therefore classifying these into Class II,
as a unit, both polymeric and titanium, into Class II category, I have a
difficulty not only as a surgeon, but also as a scientist, because these
polymeric devices are -- they behave differently.
And
all the points that Dr. Li has made are very valid. In addition to not having fracture data, which is a big issue
here, the wear of PEEK material, there is no wear data.
I
mean, you know, you may have a solid fusion, your clinical results are
great. But if the device is broken, and
if it does wear in-site, it could resorb the bone again. So it could regress.
Therefore
I don't think that we are talking about equal devices here. I think that it may be best to divide these
into two separate devices, polymeric devices, and metallic devices, and put one
in Class II.
And,
I don't know, as far as the other two, as far as the polymeric devices maintain
them as Class III, even though the spinal body devices have been approved to
date. I mean, I wasn't there on that
panel, but I have to speak my mind today.
So
I think we are talking about two different things. That is my general comment, that is my general tendency. And I think that in light of the paucity of
clinical data presented, I mean, all the industrial presentations today have
pointed to metallic cages, more than anything else.
When
one asks about polymeric cages, I can't get any intelligent answer. So, therefore, I'm a little frustrated in
pulling these two components, and downgrading them both into Class II.
So
it is my opinion that it should be divided into two. Thank you.
CHAIR
YASZEMSKI: Thanks very much. And I think to make it a little easier to go
around, we will go around to everybody
on the first part of question one, and we will change the slide to the second
part of the question and go around again.
Dr. Larntz?
DR.
LARNTZ: What is the first part of the
question?
CHAIR
YASZEMSKI: The one that is up on the
screen now.
DR.
LARNTZ: The description?
CHAIR
YASZEMSKI: Yes, sir.
DR.
LARNTZ: I agree with the description. CHAIR YASZEMSKI: Good, thank you. Ms. Wells?
MS.
WELLS: I agree with Dr. Naidu.
CHAIR
YASZEMSKI: Thanks very much. Ms. Maher?
MS.
MAHER: I actually disagree with Dr.
Naidu, and I disagree for several reasons.
There is a long history of having the same classification for different
materials that are being used.
And
a good example is vertebral body replacement devices, which are used for almost
the identical indication as this, or very similar anyway. They are Class II and it is my
understanding, while I'm not in that industry, that they are both polymeric and
metal vertebral replacement devices on the market, with not a huge issue with
them with fracture or anything else.
And
I think, I don't know the right person to call on, in the audience right now,
to talk to that, that has polymeric BPRs, or polymeric cages, but I think that
would be a good time for somebody to come up and talk to us a little bit about
what else is out on the market in Class II.
CHAIR
YASZEMSKI: And perhaps we can be
thinking about that and go around the table, and then we will call on somebody
in the audience at the conclusion of the comments from the Panel.
Dr.
Witten, if you have something to comment I would like to ask you, but I am
going to come specifically to you at the end, if you could. Dr. Cheng?
DR.
CHENG: I just note in the
identification of the device, it is, in addressing the manufacturer's concerns,
it is inclusive, the statement says including titanium alloys and polymeric, it
is not an exclusive statement, and does not state that the cages have to be
made of these.
So
it is a rather inclusive statement. In
fact, from comments today, I wonder if it shouldn't be revised to be more
specific. And the second issue is, if
one splits the category as Dr. Naidu and, I believe, Dr. Li are suggesting,
that essentially means that you are looking at two down classifications into
Class II. You would have to address all
these questions separately. Is that
correct, Dr. Witten?
DR.
WITTEN: Yes.
DR.
CHENG: Yes, okay.
CHAIR
YASZEMSKI: Thank you. Dr. Finnegan?
DR.
FINNEGAN: Well, given as how you have
us way ahead of schedule, I don't have a problem with dividing into two, and I
actually agree with Dr. Naidu. I think
that needs to be done.
CHAIR
YASZEMSKI: Great, thank you. Dr. Li?
DR.
LI: I agree with Dr. Naidu, and also
Dr. Cheng, that the description is basically completely open ended in a variety
of materials, and basically opens us up to absolutely everything.
And
we've only really had two materials that have actually any data, on the
titanium alloy and specifically PEEK, that is carbon reinforced. We have no data for any other material, or
material combinations.
I
think the device description is way too broad.
CHAIR
YASZEMSKI: Thank you, Dr. Li. Dr. Diaz?
DR.
DIAZ: Well, I hate to be the dissenting
person on this table, but I disagree with Dr. Naidu. The ultimate accomplishment of the device will be to achieve
fusion. The success of the operation is
predicated in the device providing sufficient support to last for long enough
for the bone to be formed into a solid union.
The
success of the device is not predicated on the device being forever supportive
of the body weight. And there is
additional bony material that is placed there by the surgeon to achieve that
structural stability, ultimately, frequently supplemented by internal fixation
and by external forms of support.
So
I really do not believe that the fact that one is metal, and the other one is
not metal really, ultimately, will give us what we want out of the device. So I think that division is, in theory, good
but, in practice, unnecessary.
CHAIR
YASZEMSKI: Thank you, Dr. Diaz. Ms. Anderson, can we put up slide two?
MS.
ANDERSON: Yes.
DR.
LI: While she does that can I ask Dr.
Diaz a question?
CHAIR
YASZEMSKI: Go ahead, Dr. Li.
DR.
LI: In the devices that are polymeric,
where you say the bone shares the load with the device if fusion is successful,
is there any biomechanical data that tells you how much load is taken by the
device, and how much load is taking by the bone that grows in?
DR.
DIAZ: If you use just the device alone,
in the biomechanical testing that has been done for the polymeric device, the
modulus of elasticity is equivalent to cortical bone. And so it is comparable to normal human bone.
The
metal is ten times more rigid and, in fact, it is less successful at achieving
fusion because it does not allow for sharing of weight, but it prevents the
sharing. So if anything you want the
device to allow for load sharing, rather than preventing it.
DR.
LI: My question is, do you have a sense
for how much load is shared, is it ten percent, fifty percent, ninety percent?
DR.
DIAZ: I don't think I can answer that.
CHAIR
YASZEMSKI: Thank you. We are going to
continue on around now with Dr. Naidu, the second part of question one is up on the board for us to read. And I will ask everybody, again, to go
around the table and comment on it, if they would like to do so.
DR.
NAIDU: I agree with the intended use.
CHAIR
YASZEMSKI: Dr. Naidu, thank you. Dr. Larntz?
DR.
LARNTZ: I agree.
CHAIR
YASZEMSKI: Thank you. Ms. Wells?
MS.
WELLS: I agree.
CHAIR
YASZEMSKI: Thank you. Ms. Maher?
MS.
MAHER: I agree.
CHAIR
YASZEMSKI: Thank you. Dr. Cheng?
DR.
CHENG: I agree.
CHAIR
YASZEMSKI: Thank you. Dr. Finnegan?
DR.
FINNEGAN: I have problems with point
four. I think that allograft probably
should be considered, and I really think that the surgical approach should be
left up to the surgeon.
CHAIR
YASZEMSKI: Thank you, Dr.
Finnegan. Dr. Li?
DR.
LI: My only comment, I generally agree,
my only comment would be if you are going to do testing on these devices that
the loads in the lumbar area are significantly higher than the cervical. So if you are going to do some mechanical
testing, to cover all bases, you probably want the mechanical testing loads to
be done either appropriate to the device, which means if you test it for
cervical use it may, in fact, not survive the lumbar use.
But
if you pass the lumbar use it probably would survive the cervical use.
CHAIR
YASZEMSKI: Great. Thank you, Dr. Li. Dr. Diaz?
DR.
DIAZ: My only concern here is that I
think that limiting the location, or the site of application of the device is
somewhat restrictive because, basically, what we are doing in practice in
surgery is we want to have the availability, and the opportunity to replace as
many of these things as need to be replaced.
And
restricting the use of these devices to very defined areas I think is
artificial. It is not the way medicine
is practiced.
CHAIR
YASZEMSKI: Thank you, Dr. Diaz. Dr. Cheng?
DR.
CHENG: It seems to me, though, that
from Dr. Witten's directions that we can only down classify what has already
been approved. It doesn't mean you
can't do that, it just means when you do it it is an off-label indication for
the product. Is that correct?
DR.
WITTEN: Well, I would say,
additionally, that is right. What you
said is correct, and what I said additionally is that this would leave it open
to someone to, you know, come in with an application that had a different
level, or a different bone use, for example.
But
they would need to show that they were substantially equivalent.
DR.
CHENG: Right. So although Dr. Diaz' concerns are germane, it doesn't -- I don't
think it limits the surgeon.
DR.
DIAZ: No, I understand that. I just wanted to make sure that the point
was brought up on the table.
CHAIR
YASZEMSKI: All right, thanks, Dr. Cheng
and Dr. Diaz. Now, because I ask the
question of Dr. Witten, the proposal was made before by Ms. Maher that,
perhaps, an industry representative would like to speak, and she specifically
mentioned Mr. Christianson of OSMA.
Are
you here in the audience, Mr. Christianson?
And if so, would you like to speak?
We welcome you to do so if you would like. And, again, the usual, identify yourself, etcetera, etcetera.
MR.
CHRISTIANSON: Thank you, Dr. Yaszemski. I'm Bill Christianson, I'm the vice
president of Clinical and Regulatory Affairs with DePuy Spine. And I'm also president of OSMA, the
Orthopaedic Surgical Manufacturers Association.
However,
to answer the questions that some of the Panel members have raised, I will be
answering on behalf of DePuy Spine. My
company is the one who is currently the PMA holder for one of the polymeric
interbody fusion cages.
And
I would like to answer some of the questions that I heard, and perhaps where
there might be some open questions, yet.
First of all, with regard to testing.
There
is an ASTM test standard for interbody fusion cages, it does address static and
fatigue testing. And that same standard
is applied to polymeric and to metallic cages.
So any cage that would be cleared by the FDA would have to pass this FDA
test standard.
And
there are mechanical engineers at the FDA who sit on these same ASTM
committees, so FDA's concerns are reflected in the testing that is done. The testing is very rigorous, fatigue is
applied in compression shear so it is worse case scenario for the interbody
fusion cages, and the polymeric designs are designed to withstand that.
Even
though I agree they have different performance characteristics than metallic
cages do, nevertheless they do withstand normal lumbar spinal loads in this
ASTM test methodology. And the loading
standards are different for the cervical and the lumbar devices.
So
FDA recognizes that the loading scenarios are different. Second, I heard multiple questions about
particles, and particles being bad, for example. My company performed animal testing before we went into humans
with these polymeric cages, sacrificed the animals at 6 months, 12 months, 24
months, had an independent pathologist look at the slides, looking specifically
for particulate debris.
While
a few particles of debris were found, there was no indication that there was
any adverse histological response associated with that. In addition there are several peer review
publications, in the literature, on retrieved cages, primarily failed cages.
And
the pathologist there does comment on the presence of particulate. And, again, has never noted the, what I
presume your concern is, is osteolysis associated with the presence of cages. So there are polymeric and metallic cages
out there, particles have been noted in all those instances.
And
the type of osteolysis that one sees in hip and knee implants has not been
noted to date in the spine. Are there
any other particular polymeric related questions that perhaps I could answer,
since I'm familiar with the work that my company has done?
CHAIR
YASZEMSKI: Thanks, Mr.
Christianson. Any panel members have
questions for Mr. Christianson? Dr.
Finnegan.
DR.
FINNEGAN: I have two. Do they look at lymph nodes when they looked
at particulate matter?
MR.
CHRISTIANSON: Yes, in the animal study
that we did, before we went into humans, we did total organ sacrifice. So we looked at all the filter organs, we
looked at spleen, liver, and lymph nodes.
And
in none of those cases did we find any material outside the immediate region of
the interbody fusion devices in the sacrificed animal.
DR.
FINNEGAN: And my second one is in your
clinical studies do you have posterior fixation with your devices or not?
MR.
CHRISTIANSON: For the product that we
currently have approved we do have posterior fixation. However, we have two devices in IDE right
now that are stand-alone anterior devices.
One of the lumbar spine, and one of the cervical spine.
CHAIR
YASZEMSKI: Thank you. Dr. Naidu?
DR.
NAIDU: When you say particles from
retrieved specimens, were these components intact, or were they fractured?
MR.
CHRISTIANSON: In the case of the
polymeric components they were intact.
And I can't recall, in my review of the literature, ever seeing a report
of a fractured metallic device.
DR.
NAIDU: So they were not fractured
polymeric components that were wearing?
MR.
CHRISTIANSON: That is correct.
DR.
NAIDU: -- particulate debris from an
intact component that was retrieved, and you are talking about peripheral
particulate debris?
MR.
CHRISTIANSON: Yes. There is one report, in the literature, of a
fractured particular cage that came from Sweden. These products have been available in Europe since about
1991. And there was a report of one
case from Sweden where there was an infection at the treated level, a failure
to fuse, and the cage fractured in situ in the post-operative period.
That
histologic sample was reviewed by the same pathologist whose report on the
retrieval studies, and while there was copious production of particulate debris
associated with the fractured cages, he saw only histological signs consistent
with the infection, and none that would suggest to him that an osteolytic
process, related to the particulate present in that level occurred.
DR.
NAIDU: I don't know how you can
determine that from a pathological viewpoint because infection in particulate
debris you will have white cell infiltration, you will have giant cell -- I
don't know how you can make that as a pathological diagnosis, I don't see how
you can differentiate the two.
That
is the first issue. My second question
is, you were talking about static and fatigue testing. We are talking about a different issue,
fracture toughness. Is there anything
with fracture toughness done on these polymeric components?
MR.
CHRISTIANSON: I'm not an engineer, I do
know that the static fatigue test is an array that is very similar, that is
performed on metallic devices. But I
don't know specifically what this fracture toughness standard is.
So,
perhaps, that is something that could potentially be developed through the ASTM
process.
CHAIR
YASZEMSKI: Thank you. Other questions? Dr. Li?
DR.
LI: On your instances where you have
seen polymeric wear, but no osteolysis, what was the follow-up time on those?
MR.
CHRISTIANSON: The animals that we
sacrificed were sacrificed at six, twelve, and twenty four months. So twenty four months was the length of follow-up
there.
On
the retrieved specimens the length of time that I recall, from reading the
literature, is anywhere from three to six months at the short end, to somewhere
in excess of 36 months.
DR.
LI: Because typically, like in a
polyethylene case, where there is probably more wear, it takes three to five
years for osteolysis to occur. So not
too surprising that at short times no osteolysis was visible.
MR.
CHRISTIANSON: The IDE subjects from my
company were first implanted in '91, and there is a report, in the literature,
from the developing surgeon on the ten year follow-up on his particular series
of cases.
And,
again, he is not reporting any osteolytic activity that he has seen. That is a single surgeon series, however,
that is not the whole study.
DR.
LI: And your animal test, just for
detail, was there a control, for instance polyethylene, where you know you are
going to get osteolysis in that same time period?
MR.
CHRISTIANSON: There was not. These were consecutive series of animals
where the control was allograft bone in this particular series, not
polyethylene.
DR.
LI: Thank you.
CHAIR
YASZEMSKI: Thanks, Mr. Christianson,
for your commentary. Dr. Witten, I'm
going to ask if I may ask you a question before we ask if we've answered you.
As
you have seen, there is a wide spectrum of opinion among the Panel members on
question 1 that the FDA has posed to us.
The main disagreement appears to be with respect to whether metallic and
polymeric devices can be treated the same, or whether they should be separated.
And
I'd like to ask your counsel, from the
FDA perspective, as to whether should the Panel agree that certain testing,
certain controls are necessary, that those controls could they, from the FDA's
perspective, be appropriately applied so that devices of all materials are
covered, and some don't get treated differently under a blanket decision.
Or
might they need to be separated?
Because as I understood your charge to us in the beginning, our charge
is to asses whether devices can be adequately covered by special controls.
If
our concerns about fracture toughness, about wear debris, are concerns that
need to be applied to special controls, would the FDA be satisfied if those
controls were applied to materials of all compositions?
In
other words, would you need to separate?
In other words, the controls, we could say the controls need to be
made. Perhaps they might not need to be
applied to materials that are metallic.
But we could suggest to you that the special controls be applied to all
material, and then you would have your discretion as to when to invoke them.
And
I want a little bit of guidance as to whether this discussion about separation
is appropriate from the FDA's perspective, or if we can satisfy your needs by
lumping all materials together?
DR.
WITTEN: Well, I'm a little confused by
the question. But let me try to answer
--
CHAIR
YASZEMSKI: And if I see that you are
answering differently, I'll try to rephrase it a little bit.
DR.
WITTEN: What I think you are saying is
that if the Panel thinks that the risks, you know, there may be additional
risks depending on the materials but thinks these can all be reclassified, and
can suggest controls for those risks if, you know, those risks apply to the
particular devices can you do that under one classification?
CHAIR
YASZEMSKI: That is the question, yes.
DR.
WITTEN: Yes, you can do that. Now, if the Panel thinks that that may not
be the case and they need to be handled separately then, obviously, you need to
separate them.
CHAIR
YASZEMSKI: Great, thank you. Having heard that from you, have we
adequately discussed question one to the FDA's satisfaction?
DR.
WITTEN: Well, I would say yes except
for one thing which is we have a considerable respect for your expertise, too,
in this area. And if you have any
additional comments on this question, or any of the others, we would appreciate
hearing those as well.
CHAIR
YASZEMSKI: Thank you. My opinion is that there are great
differences among materials. However,
by articulating those differences we can recommend something to FDA such that
special controls can be applied to all classes of materials and that it would
be appropriate to keep them together.
That would be my opinion.
We
would like now to proceed to question number 2. Ms. Anderson? We are
going to start this time once it is up, and everybody has had a chance to read
it, with Dr. Larntz and continue to go on a clockwise fashion.
Question
two, discuss any specific preclinical testing criteria you believe are needed
to characterize interbody fusion devices.
Dr. Larntz?
DR.
LARNTZ: Well, first of all I take the
point of view that since this device is very similar to a vertebral body
replacement device, that the testing that is done for that device should be the
starting point for our testing that is done for this.
So
in looking at the 510(k) guidance I would say that you are certainly going to
need to do the testing that is labeled there, the fatigue testing, the static
testing.
I,
of course, have to say, I of course say if you are doing SN curve, and you are
only doing it at maximum load, I think that is difficult to get a curve out of
that, if you do it at one point. It
says to do six samples.
You
know what I'm going to say. I'm going
to say you are going to have to do more samples than are in here to get a real
valid reading on that. But I realize
that this is the standard that has been set before. I just don't agree with the standard and the amount of testing
that is required.
And
I think I've said this before, I will say it again, probably before we are
through. But the fatigue testing, the
static testing, and the additional testing that is specified for vertebral body
replacement, which includes static compression, compression bending, dynamic
compression, compression bending, static torsion, dynamic torsion, expulsion,
and the exceptions that are listed there.
And
I actually, since these devices, my understanding and if I understood Dr. Diaz
correctly, these devices are basically the same, or very close to the same
devices. So it seems to me that the
testing should be the same, or very close to the ones that we already have
here.
And
I don't have additional ones to add.
CHAIR
YASZEMSKI: Great, thank you very much,
Dr. Larntz. Ms. Wells?
DR.
WITTEN: I have no comment.
CHAIR
YASZEMSKI: Thank you. Ms. Maher?
MS.
MAHER: I would actually like to agree
with Dr. Larntz for one of the first times.
CHAIR
YASZEMSKI: Thank you. Dr. Cheng?
DR.
CHENG: No, I think the mechanical
testing is the issue in the preclinical test.
CHAIR
YASZEMSKI: Thank you. Dr. Finnegan?
DR.
FINNEGAN: I will agree with whatever
Dr. Li --
(Laughter.)
CHAIR
YASZEMSKI: Dr. Li, you are up.
DR.
LI: With that pressure filled statement
-- I think the thing, the specific thing I would like to add is the fracture
toughness testing. And I would also --
I don't believe that what I think I read has the worse case scenario for
loading in these tests is actually the worse case scenario.
I
think the loading and the positioning, I can think of several probably
clinically relevant conditions that would present much higher demands to the
device than what the test currently asks for. So my two specific would be that --
and, again, this is really not disparaging, in any way, the -- I want to say
this many times.
I'm
not disparaging, in any way, the current devices that are on the market. I'm just going to assume they work as
everybody says. I'm really worried
about the next device coming down the pike.
And
I think to make sure that we continue to have this excellent result, you are
going to need fracture testing, and increase the demands on the actual dynamic
testing.
CHAIR
YASZEMSKI: May I ask, Dr. Li, what would
your opinion be regarding testing for different portions of the spine? Would
you suggest, for example, a test that would be adequate and appropriate to
serve in the lumbar spine, and have all devices meet that, or would you suggest
separate fracture toughness criteria for lumbar and cervical applications?
DR.
LI: Well, I guess I can answer that two
ways. I would prefer to have separate
requirements because I hate to over demand a device. But then if Dr. Diaz wants the option of taking a device that was
meant for the cervical area, and using it in the lumbar, then I would just
presume that everything should pass the lumbar.
I'm
not saying that you would do that, Dr. Diaz, but someone might be tempted to,
in fact, use the device in a place that it wasn't intended for.
CHAIR
YASZEMSKI: And for these applications,
may I ask you one more question, do you feel that the fracture toughness and
fatigue testing would be okay, or would you also do the load to failure testing
that is currently done, and have the complete series?
DR.
LI: I would not take away any
resistance test, and I would add the other two tests.
CHAIR
YASZEMSKI: Okay, thank you. Dr. Diaz?
DR.
DIAZ: I agree with what Dr. Larntz
said. I think that basically capsulizes
my thinking.
CHAIR
YASZEMSKI: Thank you. Dr. Witten have we adequately addressed
FDA? Our opinion seems to be more
uniform on this, that the existing testing is appropriate, and that the
addition of fracture toughness testing would be a recommendation that we would
make to FDA.
Have
we adequately answered your concerns on question number 2?
DR.
WITTEN: Yes. I was just wondering, Dr. Naidu, since we started with Dr.
Larntz?
CHAIR
YASZEMSKI: I'm sorry, Dr. Naidu, I
apologize for not coming back around to you.
Dr. Naidu, comments?
DR.
NAIDU: Well, I agree with Dr. Li as far
as adding the fracture toughness. But
the only other issue that I am concerned about is when this device does
fracture, the device, the components rubbing on each other becomes a big issue.
Neat
PEEK is very soft, and so I think particularly debris also needs to be studied.
And neat PEEK is not -- the particulate debris is not benign. And even though the published literature may
not state so, it is not benign. It is
in my thesis, I can show it to you later.
CHAIR
YASZEMSKI: Thank you, Dr. Naidu. Dr. Witten, I will now add, let me ask Dr.
Cheng, if Dr. Cheng has a comment. Go
ahead, please.
DR.
CHENG: I was just thinking about all
the discussion we had about the differences in materials, but there hasn't been
much discussion about the difference in geometry. And that, of course, makes a big difference in what we've just
been talking about.
And
so I think that these tests will cover all these issues and perhaps the separation
of materials is not as important as we were saying because, obviously,
regardless the material is going to have to pass the test.
CHAIR
YASZEMSKI: Thanks, Dr. Cheng. Other comments?
(No
response.)
CHAIR
YASZEMSKI: Dr. Witten, I will append to
my prior description of Dr. Naidu's comments that, perhaps, one should consider
that if a device fractures, that wear debris tests might be an appropriate part
of the test armamentarium.
With
that, have we adequately answered FDA's concerns on question number two?
DR.
WITTEN: Yes, thank you.
CHAIR
YASZEMSKI: Thanks very much. Ms. Anderson, may we ask for question number
3? And we are going to start with Ms.
Wells once that is up. And I will try
to include Dr. Larntz when I come around.
MS.
ANDERSON: I'm going to switch the
slides so it presents the risks that we've already identified, so you can just
add to them.
CHAIR
YASZEMSKI: Okay. Please discuss the risks to health for the
intervertebral body fusion device.
MS.
ANDERSON: You can go start discussing,
and I will switch slides as quickly as I can.
MS.
WELLS: At this point, representing the
consumer, the issues that were brought up, as far as patient selection was
concerned, and as far as clinical satisfaction on the patient end, again, that
has a lot to do with the physician and the surgeon, and which device is
implanted.
As
far as the classification I really don't see -- I don't have any additional
comments.
CHAIR
YASZEMSKI: Thank you very much. Ms. Maher?
MS.
MAHER: I don't have any additional
comments at this time.
CHAIR
YASZEMSKI: Thank you. Dr. Cheng?
DR.
CHENG: I think my only concern is that
we have looked at the risks from the papers that have been described, but all
of them, the length of follow-up for the length of time that the device has
been implanted in their trials, either for the FDA required trials, or other
ones.
And
so I think there might be some long term ones that we are not looking at. And, as I said earlier, my main concern
would be adjacent segment disease. And
I have to think, in spite of what Dr. Diaz is trying to reassure me with, he
also stated that some devices are more rigid than others.
And,
therefore, I have to think that the risk of, if that is clinically significant,
then the risk of adjacent segment disease is going to be higher, perhaps with
more rigid devices, than with devices that aren't as rigid.
CHAIR
YASZEMSKI: Thanks, Dr. Cheng. Dr. Finnegan?
DR.
FINNEGAN: I'm going to pick up on
something that Ms. Wells said. I think
that the surgeon is really important in this, both for patient selection, which
has been discussed, and also the technique.
And
I understand that training is "a resource drain on the company", but
in Texas we call that cow paddies, because they get major benefits from contact
with surgeons, contact with patients, everything else.
So
some form of company contribution to training until this is a regular part,
spinal surgery training I think would be appropriate.
CHAIR
YASZEMSKI: Would you think it
appropriate that any such training be required, or should it be at the
discretion of the surgeon and/or the company?
In
other words, if the company wants to make it available, great. And if the surgeon wants to take it,
great. Or would you want anything more
than that?
DR.
FINNEGAN: I agree that NASS and the
Academy, and a few other groups have facilities to do this. This is really expensive, especially if you
go to cadaveric work. And, therefore,
my recommendation would be that the companies assist in educating the spinal
population.
And
I would, actually, suggest for this particular thing, because it is different,
and it technically can be catastrophic, that it be recommended.
CHAIR
YASZEMSKI: Thank you. Dr. Li?
DR.
LI: I have nothing to add to that list
of risks.
CHAIR
YASZEMSKI: Thanks very much. Dr. Diaz?
DR.
DIAZ: I agree wholeheartedly with Dr.
Finnegan. I would be, perhaps, a little
bit more emphatic that it is the responsibility, in a way, of the companies to
bring all the people who want to complete this type of surgical procedure to
really be, if not supported, at least somehow assisted in acquiring the
education.
It
is ultimately to their benefit to see that it gets done properly.
CHAIR
YASZEMSKI: Thank you. Dr. Diaz, may I ask you an additional
question? Could I ask you to comment on
Dr. Cheng's potential concern about adjacent segment disease?
DR.
DIAZ: Yes. I still go back to the same statement I made earlier. The end result is going to be fusion, and
the fusion is going to be achieved by either device.
The
effect on adjacent segment disease is not immediate, it is a process that
evolves over the course of months or years.
And so if that is the way it is going to happen, it usually will happen
after the fusion is complete irrespective of whether the cage is metal or PEEK.
DR.
TROMANHAUSER: Thank you. Dr. Naidu?
DR.
NAIDU: All my concerns have been
expressed previously, I have nothing else to add.
CHAIR
YASZEMSKI: Thank you. Dr. Larntz?
DR.
LARNTZ: No additional comments.
CHAIR
YASZEMSKI: Thanks very much. Dr. Witten, there again seems to be a
convergence of opinion on question number 3, that the surgeon is a very
important link here, and that it would be good if some attention were paid to
training him or her, and providing education in the use of these devices.
A
concern was brought up about the potential for adjacent segment disease. And the idea was put forth that that is
going to occur after a fusion, most likely, and be little effected by the
properties of the device that is used to achieve that fusion.
Have
we had adequate discussion on this issue, from FDA's perspective?
DR.
WITTEN: Yes, thanks.
CHAIR
YASZEMSKI: Thanks very much. We are going to go to question number 4 now.
MS.
ANDERSON: Actually question number 4 is
so closely related to question number 3 I believe you've already answered it.
CHAIR
YASZEMSKI: Then I will go right to Dr.
Witten. Dr. Witten, question 4, discuss
any other risks to health.
DR.
WITTEN: I was thinking that you had
answered that.
CHAIR
YASZEMSKI: Have we had an adequate
discussion to satisfy FDA, or should we go around the table one more time?
DR.
WITTEN: I think it would be -- you
might just ask if anybody has anything to add, because some people were
discussing these risks, and some people were discussing those risks.
CHAIR
YASZEMSKI: So asked. Does anybody want to talk about anything
else related to health?
(No
response.)
CHAIR
YASZEMSKI: Seeing none, Dr. Witten,
have we adequately discussed this? Ms.
Anderson, can we go to question five?
MS.
ANDERSON: You like watching me go up
and down.
CHAIR
YASZEMSKI: The question, as she is
putting it up is, do you believe special controls can be developed to
adequately control the risks associated with this device? Ms. Maher?
MS.
MAHER: I believe that the special
controls in the form of a guidance document similar to the guidance document
for vertebral replacement devices would be sufficient to control the risks.
CHAIR
YASZEMSKI: Thank you, Ms. Maher. Dr. Cheng?
DR.
CHENG: I do think special controls can
be enacted but I think the -- maybe it is more a process issue, not germane to
just -- not limited to just this device.
And that is the MDR, for so many of the devices that we implant, as
surgeons, and we see the complications related to some of them years later.
I
personally have done many operations where I am not -- I don't actually know if
I had to fill out an MDR on a certain device.
So there needs to be an improvement in the MDR process because the current process, as it exists, is
useless.
And
it does not achieve the objective that is stated.
CHAIR
YASZEMSKI: Thanks, Dr. Cheng. Dr. Finnegan?
DR.
FINNEGAN: I'm going to be a royal pain,
again. Dr. Witten, I have a
question. How come GE knows I have
their dishwasher, but nobody in this room, sitting in the audience, knows that
I have a plate?
I
mean, technology now is such that device tracking should be a no-brainer. So I think that we need to look at device
tracking, specially with these devices.
DR.
WITTEN: And when you say tracking do
you mean that the sponsor should be able to track the devices?
DR.
FINNEGAN: Somebody needs to know, I
mean, my question is basically GE knows I have their dishwasher. But you don't know I have a plate in my
arm. And my question is, why?
CHAIR
YASZEMSKI: Dr. Witten, if you want to
think about that while we go around the room, fine. If you want to answer it now, go ahead.
DR.
WITTEN: Well, I'll just say that if
there is some -- I can't really answer it generally. But if there is something
specific that you think that is needed here, you know, we would certainly be
interested in knowing what that was, and why, for this particular group of
devices.
DR.
FINNEGAN: Well, I guess we could start
with this particular group of devices.
Because if, as the concern is, there is wear particles, and we see in
ten years that we have huge osteolysis and some cord problems, then a lot of people
are going to be unhappy.
So
I think the risks here are potentially significant. And I think the reason for having a device data base, and device
tracking, is because right now surgeons don't, you know, don't always know. Somebody has to go back through the chart
and see if the patient has the device.
So
that, basically, it is recall long-term complications. And there are phenomenal examples. There are the pores that came off the first
Hungerford micropores. There is the
polyethylene in acetabular components.
I
mean, there is just -- we have been through this so many times, and the
information technology now is such that we really probably need to take this
seriously.
CHAIR
YASZEMSKI: Thanks, Dr. Finnegan. Dr. Li?
DR.
LI: Yes, I agree with Dr.
Finnegan. We are asked -- this
reclassification is a little different than the previous ones I have been on, I
have been on the bone cement, and the metal on metal one, where there actually
was a much longer time period of clinical follow-up, you know, some times 20 or
30 years in the case of bone cement.
But
here we are asked, actually, to reclassify a device that I think the longest
follow-up I saw on one of our papers was four years, but that was only 11 out
of 947 patients.
So
the vast majority of the data is two years and less. Now, it just raises a
question about what the long term -- so I don't really know what special
control you could add, other than if you could follow these patients up
somehow.
The
other issue that, again, I also don't know what to do about, is that these are
fusion devices with no laboratory test for fusion. So these devices are, apparently, working great the way they are.
Again,
my worry is in the future. I don't know
what special control that would be, because there is no laboratory model for
fusion, not that I can think of, or that I'm aware of.
So
the two worries are that we don't know what the long term results are, but I
don't know what the special control would be.
And we don't have any way to measure fusion. But, again, I don't know what the special control would be.
And
perhaps a way around this issue of do you test everything the same, is to have
two guidance documents. In other words,
you could have -- because I would hate to test a material like a metal for
problems that are only going to happen on a polymer. I don't think that is actually reasonable.
So
maybe the solution around this is to have two guidance documents, one for a
metallic component, and one for a non-metallic, for instance.
CHAIR YASZEMSKI: And then we have the ability to suggest to FDA that they do that.
DR.
LI: Right.
CHAIR
YASZEMSKI: Thanks, Dr. Li. Dr. Diaz?
DR.
DIAZ: In general I agree with the
comment of having the same standards that are used for the interbody vertebral
replacements as the basic process of assessment.
In
regard to Dr. Finnegan's comment about tracking of these devices, by the
company, being an attorney as well, and knowing HIPAA, currently HIPAA
prohibits any company having any clinical information pertinent to the patient.
And
perhaps we need to go back to HIPAA and change that. But until that is changed I don't think we can ask the companies
to provide us with tracking of devices that they are not legally allowed to
get.
And
the third comment is the issue of these being fusion devices. They are not
fusion devices, they are spacers. The
fusion devices is the autograft, or the allograft that is placed to exert the
fusion and become osteo-conductive for the body to eventually complete the
fusion.
The
device is purely a structural gadget that allows the space to remain the same
until the body forms bone osteoblasts and completes the process of fusion. The device doesn't do the fusion.
DR.
LI: Can I ask a question of Dr. Diaz?
CHAIR YASZEMSKI: Go ahead, Dr. Li.
DR.
LI: Do you believe, then, that the
design of the material has nothing to do with fusion, then?
DR.
DIAZ: No, that is not what I said. In the prior comments I have indicated that
the metal device is a load bearing. So
it is less likely to allow a fusion than the load sharing that the PEEK allows.
It
is more successful with the load sharing device, than with the load
bearing. But the fusion itself is
really not the result of the device, it is the result of the available
osteoconductive tissue that you put in between the device and the two bony
surfaces, and ultimately the ability of the bone, or the human body to complete
the fusion.
DR.
LI: Not to quibble over nomenclature a
little bit. So what you are telling me is that the modulus of the material
plays a role in the fusion?
DR.
DIAZ: It facilitates it greatly, yes.
DR.
LI: Correct. So that tells me that there is a material property, or design
aspect of the device that influences the amount of fusion.
For
instance, you would probably be against me giving you a cage with a higher
modulus than titanium? As an example.
DR.
DIAZ: Well, in general terms you are
correct. In the detail of how this
happens is, perhaps, minuscule in reality, and probably beyond the scope of
what we are discussing.
CHAIR
YASZEMSKI: Thank you, Dr. Diaz. Dr. Naidu?
DR.
NAIDU: All of my thought have been
discussed adequately.
CHAIR
YASZEMSKI: Thank you, Dr. Naidu. Dr. Larntz?
DR.
LARNTZ: This issue is difficult for me
because I look at the examples we have, and I look -- the examples we have are
actually, we have all successful examples.
And I'd like to know if these
tests can pick out a cage that will fail.
And
I don't know that because I don't have examples of failed cages, and their
mechanical, and pre-clinical, and all testing.
So it is a case where we are trying to pick out, it is like all the
people with prostate cancer are males, so male must be the reason, you know?
So
-- and it is to a certain extent. There is other problems there, to. So I don't, I have real trouble thinking of
what is going to be predictive of failure. And I know, I think I'm in a
position where I'm going to say I don't have anything to add, except I'm
actually disturbed, if I might say, that the vertebral body replacement was
Class II, when this was Class III.
If
I heard the comment correctly, it is a more risky replacement than this one, if
I heard the comment correctly this morning. Well, that is a different issue, I
guess.
So
I guess I don't have anything to add. I
worry about not suggesting clinical data of some sort, as a -- it is always a
possibility, I think. And it is a
possibility even with 510(k) to suggest clinical data.
And
with respect to fusion, the way we measure fusion is we put these devices in
people, and then we do some flexion extension, I'm sorry, CTs, or whatever we
do, okay? But that takes -- well, some
people say it takes six months if you do it in the cervical, and a year in the
lumbar.
But
the FDA seems to say two years, right?
Isn't that what we've always had, I think? And so if they are really fusion devices, then the only way to
test for fusion, that I know of, is clinically.
And
so I'm torn between saying, gee, these things seem to be pretty safe,
everything seems to be pretty good. But, again, I don't know what the failed
devices are like. And then saying, it
seems to me that there is a potential for devices not working, that we probably
missed, by the kind of testing that we have.
So
I guess I will stop with those general comments that don't add anything.
CHAIR
YASZEMSKI: Thank you, Dr. Larntz. Ms. Wells?
MS.
WELLS: I have no additional comments.
CHAIR
YASZEMSKI: We are going to go, we are
going to end where we started, with Ms. Maher.
MS.
MAHER: I have a few additional comments
to make. First, regarding vertebral
body replacement devices, versus cages.
The cages first came on the market after 1976, so they would
automatically have gone into Class III, while the other product was a Class II.
I
believe that the interbody replacement device gives us further evidence as to
why this device could, very successfully, be placed into Class III, and the
risks ameliorated by the special controls, such as already exists for the
vertebral body replacement.
Regarding
device tracking, as a patient, most patients don't want to be tracked. And, for instance, GE knows where your
dishwasher is. They do not know where
it is if you move. They know where it
is, they don't know where you have gone.
These devices traVel with these
patients.
Device
tracking is a very, very difficult thing to do, to maintain where these
patients are and, I think, should only be done in cases where there is a sever
risk to patient health, to be able to find these patients quickly, such as a
heart valve.
I
would have a hard time supporting any other reason for device tracking. Thank you.
CHAIR
YASZEMSKI: Thanks, Ms. Maher. Dr.
Witten, again we have general consensus on this issue, that perhaps special
controls can be put into place and the suggestion was made that a potential way
to do that may be separate guidance documents for different types of device
within the general Class II classification.
There
was some concern given about long term follow-up, some concerns about tracking,
on both sides. Have we, adequately,
discussed this, from your perspective at FDA?
DR.
WITTEN: Yes, thanks.
CHAIR
YASZEMSKI: Thanks so much. What I would like to suggest that we do now
is break for lunch. It is almost 20
minutes after 12. Perhaps we can take
about 45, 50 minutes or so, and try to get back about 1 o'clock.
We
will start, when we come back, filling out the questionnaire and supplemental
data sheet, and then we will proceed to a vote.
Mr.
Melkerson, do you have a comment?
(No
response.)
CHAIR
YASZEMSKI: Okay, let's break for lunch
now, for 45 minutes.
(Whereupon,
at 12:19 p.m., the above-entitled matter was recessed for lunch.)
A-F-T-E-R-N-O-O-N S-E-S-S-I-O-N
1:09
p.m.
CHAIR
YASZEMSKI: I'd like to call the meeting
back to order. Now that we've addressed
the FDA's questions, we will complete the classification questionnaire, and the
supplemental data sheet.
Ms.
Marjorie Shulman, of the Office of Device Evaluation, will assist us, as we go
along. Thank you.
After
Panel discussion of each question, I
will note our answer for each blank on the data sheet, and Ms. Shulman will
record it on the overhead for us. And I
think Ms. Anderson will actually do that.
We
will vote on the completed questionnaire, and supplemental data sheet, and it
will become the Panel's recommendation to the FDA. I'm going to ask about questions regarding this procedure in a
moment.
I
want to ask Ms. Maher, however, for one more comment before we move to
this. Ms. Maher?
MS.
MAHER: Thank you. I actually have three comments because I had
time, over lunch, to do a little bit of thinking. First of all I was thinking of the other fusion devices that are
out on the market.
And,
Dr. Cheng, the issues you brought up on the level above, and degenerative disc
disease, etcetera. And those other
devices are all Class II, and all raise the same issue, or potential of issues
that are there.
So
I'm not sure it is an additional risk that these devices have, that the other
cages, or rods on the market don't already have. Second, VPRs are made out of PEEK as well. As a matter of fact, VPR is made out of the
same material as their cage, and they are not suffering any of the issues that
we have brought up, and they are Class
II and did all the testing that was disclosed, earlier, for that product. So, again, I think that alleviates
some of the issues we've discussed on additional testing. Third, and this is probably the most
important point, is the FDA on a very regular basis, deals with 510(k)s that
are the next step, the next step of a design, the next -- where it is going.
And
they are very skilled at having us give them all the information that exists in
the guidance document, looking at it and saying, Sally, this is a different
indication, you need to give me more information.
The
new more information may be animal testing, it may be bench testing, and it may
be clinical testing. Or the answer may
be, Sally, this is so new you need to go do a PMA.
It
is just something that they are skilled at, and it has to be done on a case by
case basis, as they are moving forward, not something that I think we, as a
panel, can sit here and hypothesize what is going to happen two, three years,
down the road from there.
So
I just sort of wanted to summarize that all together and express my concern
that we have been going off on these tangents when, in fact, these devices
really do, from the risk and benefit of them, belong in a Class II, with the
FDA there to give the oversight when the 510(k)s come in to determine if that is appropriate for that
specific device, and that specific indication and material that they are there
for. Thank you.
CHAIR
YASZEMSKI: Thank you, Ms. Maher. Ms. Shulman?
MS.
SHULMAN: Good afternoon. First I just want to read a couple of
statements. The general device
questionnaire is designed to aid in the determination of a proper class for all
medical devices, and a medical device shall be placed in the lowest class which
will provide adequate controls to reasonably assure the safety and
effectiveness of the device.
And
the first three questions, questions 1, 2, and 3, pertain to the degree of risk
of the device, and can be answered broadly.
So with that, we can start.
We
will start, everyone will have to fill out their own form. If you can please put your name on the top,
and today's date, and all. And we will
collect everyone's form at the end. And
there will be one main form for the vote.
CHAIR
YASZEMSKI: Thank you. So let's move, are we ready to move to
question 1? Is the device life -- how
about I turn it to you and let you be the reader, if that would be okay with
you?
MS.
SHULMAN: That is fine. Number one, is the device life sustaining,
or life supporting?
CHAIR
YASZEMSKI: Dr. Cheng, how about we
start with you this time?
DR.
CHENG: No.
DR.
FINNEGAN: No.
DR.
LI: No.
DR.
DIAZ: No.
DR.
LARNTZ: No.
CHAIR
YASZEMSKI: Dr. Naidu?
DR.
NAIDU: No.
CHAIR
YASZEMSKI: We have no as the answer for
question one. Question 2?
MS.
SHULMAN: Question 2, is the device for
use which is of substantial importance in preventing impairment of human
health?
CHAIR
YASZEMSKI: Dr. Finnegan?
DR.
FINNEGAN: Yes.
CHAIR
YASZEMSKI: Dr. Li?
DR.
LI: Yes.
DR.
DIAZ: Yes.
CHAIR
YASZEMSKI: Dr. Naidu?
DR.
NAIDU: Yes.
DR.
LARNTZ: Yes.
CHAIR
YASZEMSKI: Dr. Cheng?
DR.
CHENG: I said no, I read this as
preventing impairment. Is this
preventing or treating impairment?
Maybe that is why I read it --
CHAIR
YASZEMSKI: Shall we have discussion, or
a point of order? If there is general
agreement I might make a motion that we accept the yes, and ask the person who
voted no, in this case Dr. Cheng, if you would be okay with a yes vote from the
Panel on this?
DR.
CHENG: It is perfectly fine. I just was explaining why I voted no.
CHAIR
YASZEMSKI: Thanks so much. We, as a panel, will fill in yes to question
number 2. Number 3?
MS.
SHULMAN: Number 3, does the device
present a potential unreasonable risk of illness or injury?
CHAIR
YASZEMSKI: Dr. Li?
DR.
LI: Is this the device of the ones that
we have been asked to review? Then the
answer is no.
DR.
DIAZ: No.
CHAIR
YASZEMSKI: I'm sorry, I was not paying
attention. Go ahead, Dr. Li, I didn't
get your answer.
DR.
LI: I said no, if we are talking about
the devices we got data for.
CHAIR
YASZEMSKI: Thank you. Dr. Diaz?
DR.
DIAZ: No.
CHAIR
YASZEMSKI: Dr. Naidu?
DR.
NAIDU: No.
CHAIR
YASZEMSKI: Dr. Larntz?
DR.
LARNTZ: No.
CHAIR
YASZEMSKI: Dr. Cheng?
DR.
CHENG: No.
CHAIR
YASZEMSKI: Dr. Finnegan?
DR.
FINNEGAN: Maybe.
CHAIR
YASZEMSKI: And for the point of filling
out the --
DR.
FINNEGAN: I will accept no.
CHAIR
YASZEMSKI: -- would you be okay with
no? Okay. We are going to fill out no to number 3.
DR.
FINNEGAN: Okay.
CHAIR
YASZEMSKI: Ms. Shulman?
MS.
SHULMAN: Number 4, did you answer yes
to any of the above questions, that answer is yes, so then we would go to number
6, we would skip number 5.
Number
6, is there sufficient information to establish special controls, in addition
to the general controls, to provide reasonable assurance of safety and
effectiveness?
CHAIR
YASZEMSKI: Dr. Diaz?
DR.
DIAZ: Yes.
CHAIR
YASZEMSKI: Dr. Naidu?
DR.
NAIDU: Yes for metallic, no for
polymeric.
CHAIR
YASZEMSKI: Dr. Larntz?
DR.
LARNTZ: Yes.
CHAIR
YASZEMSKI: Dr. Cheng, whenever you are
ready?
DR.
CHENG: Sorry, no.
CHAIR
YASZEMSKI: Dr. Finnegan?
DR.
FINNEGAN: I actually agree with Dr.
Naidu, yes and no.
DR.
LI: Same answer.
CHAIR
YASZEMSKI: Yes and no. Okay, well, this
is a --
DR.
DIAZ: Maybe we need a point of
clarification here.
CHAIR
YASZEMSKI: Okay.
DR.
DIAZ: Does this question mean to ask
general controls in and of themselves, alone, or sufficient?
CHAIR
YASZEMSKI: No, what this says is that
do we feel that we can implement special controls so that these devices will be
safe and effective? If we feel that
special controls, in addition to the general controls, which would exist if it
were a Class I, if we feel that special controls cannot be put in place, that
would make it safe and effective, then it remains in Class III and we are done.
If
we feel that special controls, be they for the devices all considered together,
or the devices if we look at metal and polymeric separately. If we feel that we can control the safety
and effectiveness by suggesting to the FDA special controls on these devices,
then the answer to this has to be that we say yes, and we move on to discussing
those special controls.
DR.
CHENG: I'm sorry, I read the wrong
question. The answer to number 6, in my
opinion, is yes.
CHAIR
YASZEMSKI: Well, we have some yeses and
some combination yes and nos. I'm going
to suggest, unless there is someone who strongly disagrees, that we answer this
yes, so that we can discuss those special controls, and then we will vote on
those.
Any
disagreement with me putting yes down for this?
(No
response.)
CHAIR
YASZEMSKI: We are going to put yes to
number 6. Ms. Shulman?
MS.
SHULMAN: Number 7, if there is
sufficient information to establish special controls to provide reasonable
assurance of safety and effectiveness, identify the special controls needed to
provide the reasonable assurance for Class II devices.
CHAIR
YASZEMSKI: Dr. Naidu, I'm going to
start with you, and you may, these special controls may be special controls
that you apply to the class of devices, be they metal or polymeric, or they may
be special controls that are different for the polymeric devices, or the metal
devices, as you see fit.
So
I will ask you what you think they are.
DR.
NAIDU: You mean pick one or more, is
that what you are asking me?
CHAIR
YASZEMSKI: Yes, sir.
DR.
NAIDU: Guidance document, performance
standards, I'm not sure how practical device tracking is, but it would be nice
to have that as well, and testing guidelines.
All of them.
CHAIR
YASZEMSKI: Okay, thank you. Dr. Larntz?
DR.
LARNTZ: I think special controls can be
implemented using a guidance document.
CHAIR
YASZEMSKI: Thank you. Dr. Cheng?
DR.
CHENG: I said yes to guidance document,
and I think device tracking is very important.
There is no way we can predict what will happen in the future, and if
some unknown complication develops that is the only way we can either identify
it, find it, and then notify the appropriate individuals.
And
then testing guidelines, according to the fatigue fracture, testing that we --
I'm sorry, not fatigue, fracture testing we were just talking about earlier
this morning.
CHAIR
YASZEMSKI: Thank you. Dr. Finnegan?
DR.
FINNEGAN: I would agree with Dr.
Naidu's vote.
CHAIR
YASZEMSKI: And so that is for all four?
DR.
FINNEGAN: Yes.
CHAIR
YASZEMSKI: Dr. Li?
DR.
LI: I would be for guidance document,
testing guidelines. If I could figure
out a way to do device tracking I would suggest that. The only other thing I will raise, I don't really know how to
work this in, also a study of retrieved devices.
I
mean, one of our questions is really what is the failure mode, if any,
specially in the polymeric devices. But
we have very little, if any, analysis of retrieved devices.
So,
for instance, a study of 100 retrieved devices may show no signs of fracture
and fatigue, even in large heavy occupations, in which case that would go a
long way to alleviate our concerns.
DR.
TROMANHAUSER: Thank you.
DR.
LI: My answer is retrieval analysis.
CHAIR
YASZEMSKI: Dr. Diaz?
DR.
DIAZ: I would go along with the
guidance document, the performance standards, the testing guidelines. And I
think the idea that Dr. Li just brought up is actually a very good one. It would be very simple to retrieve those
devices and subject them to testing again.
So I would add that, also.
CHAIR
YASZEMSKI: Thank you. And for point of
clarification, could we fit study, retrieval analysis study in one of the
testing, or shall we put that in other?
MS.
SHULMAN: Other.
CHAIR
YASZEMSKI: Okay, so we have a vote for
other, or a suggestion for other. I
think that to fill these out we clearly are going to have to make
recommendations to FDA as to what we would consider in a guidance document, in
a performance standard, for device tracking, etcetera.
But
I think we can get to the detail after we have completed the sheet. So I think
we are going to have to come back to this, unless you suggest we flesh out the
details of these, at the present time?
MS.
SHULMAN: Not necessarily all the
details, but we do have to flesh out the performance standard versus guidance
document. Remember, the performance
standard is the rule making, and the guidance document is --
CHAIR
YASZEMSKI: That is a good point. For those three of the voting members who
voted for performance standard, would you feel that your concerns could be met
if the items you would put in a performance standard were put into a guidance
document? Comments?
DR.
NAIDU: Yes, that should be reasonable.
DR.
FINNEGAN: I'm not sure, because we go
from sort of regulated to, you know, if the weather is right, and you feel like
it. And that is a little concerning.
MS.
MAHER: May I make a comment on that,
please?
CHAIR
YASZEMSKI: Yes.
MS.
MAHER: Sally Maher. I actually think the guidance document is
the most suitable way to go. One of the
problems, if you were to try and go performance standard are that it will take
a long time for it to be implemented, goes through notice and comment
rulemaking.
It
becomes almost like an act of God that you must do, which wouldn't allow any
growth in this technology, or industry, at all. When you say, well, guidance documents whether you want to do it
or not, that is really not a true statement.
The
fact of the matter is, from an industry point of view, we either follow the
guidance document to make sure that we can answer the questions, and even then,
quite honestly, the FDA will come back and ask us for significant more
information, because our issue is a little outside the guidance document.
Or
we write a very detailed rationale explaining why the guidance document is not
applicable to our device because of a different change in the technology to
take it to the next step, and then would provide testing or equivalent
information that will support it.
When
you go to performance standards what is going to happen is we are going to tell
them what we think it needs to say.
They are going to, eventually, enact it somewhat like an act of God that
will become a rule that happens. And it
will never change, and you will never see any advances in this technology, at
all.
I
would also like to make a comment on this device tracking concept. I'm not sure why we want to hold the Class
II devices which, as we've discussed, are very similar to vertebral body
replacement devices that are already out there in Class II, to a significantly
higher standard than they currently are as Class III, or than the DBRs are at
this time.
So
I understand some of the concerns that I'm hearing, but I'm not sure that you
all understand the implications of what you are asking for. And I honestly believe that a guidance
document that sets out the type of testing that we would like to see, the
labeling that needs to be there, etcetera, is really the best way to go.
Retrieval
of cages when they are explanted, that is great if you can get them back. You don't always get them back, they come
back some times, they don't come back other times.
Many
times if there is something that has gone on the hospital will maintain them,
because there is litigation that might or might not be involved. I'm not sure that will show a lot of
information.
But
I know, at least on the joint side, there are people that do analysis of
retrieved joints on a regular basis.
But it is not a requirement for the industry to get them back. And I don't see how you could require the
industry to get a cage back, after it has been explanted.
I
just don't see how it can happen. The
industry doesn't know when you've explanted a cage, necessarily. So I'm having a hard time seeing how that
could happen.
CHAIR
YASZEMSKI: May I ask, Dr. Witten, for
clarification on this, with respect to Dr. Finnegan's concern, that if it is in
a guidance document the industry people can do or not do it at their
discretion.
Is
that true, or is it a guidance document that still allows the FDA to insist on
certain things being done prior to giving a clearance? Can we have clarification on that, so that
we can flesh out these two?
DR.
WITTEN: Well, what a guidance document
does is it will -- it will describe what the risks are and identify a number of
ways in which the sponsor of the product can do testing to address those risks.
I
mean, there is other things, too, like device description, and so we certainly
would look at all -- if the sponsor gives us an application, we certainly would
look at all the elements.
And
I think the way we look at it is it gives a path to a sponsor for being able to
get to market that, you know, this is sort of a recipe to do your testing that
we can look at and we will have a good understanding for comparison.
It
does leave open, to a sponsor, to provide some alternative demonstration of
safety, or effectiveness, safety and effectiveness of their product.
So
I don't think it is -- I would say it gives some flexibility in the sense that
the sponsor doesn't have to follow exactly that method in order to demonstrate
the safety and effectiveness of their product.
But
on the other hand I wouldn't say it allows them to just do anything, or give us
anything they want. Now, a performance
standard, of which there is only one, as far as I know, in the history of FDA,
just to give you some idea of performance standards.
If
you know there is something about the product that you know that to be a safe
and effective product, that it must, under the following test conditions, for
example, have exactly the following results.
And that would be the case for performance standard.
So
I think that clarifies the --
CHAIR
YASZEMSKI: That does, thanks.
DR.
WITTEN: And then for tracking, I just
will say it is correct that these products aren't currently being tracked to
the patient as Class III devices, and that the other spinal implants are also
not currently tracked devices.
So
if it is something you are recommending, I think it would be helpful for us to
have an understanding of what, in this case, we are looking for. Or if it is a general statement that we
think is a general matter of policy, FDA should track all implants.
In
other words, is there something specific here that we need.
CHAIR
YASZEMSKI: Thank you, Dr. Witten. Dr. Cheng?
DR.
CHENG: Well, the answer to that
question to clarify about the device tracking, which I mentioned and others did, I think it should be tracked to the
patient. I don't think there is
anything specific to this device, as opposed to other devices.
But
I think the investment, given our current technology right now, has come down
in terms of requiring one to track to the patient. And the reason to do it,
Sally, is because if we had known about problems related to certain devices we
could have prevented the continued implantation of those devices and saved
untold costs, financial, physical, emotionally, of patients in terms of
fractured T-28 stems, catastrophic failure of polyethylene cups, those are just
two examples.
History
is replete with examples of situations where our sensitivity of any monitoring
to detect a problem in an implant or device, is not sensitive enough to pick it
up early enough so that patients are not continually harmed by the device.
If
a surgeon didn't notice the problem related to the sulzer cup problem, who
knows how long it would have taken before it would have been noticed? It was not picked up by MDRs, or anything
else.
Most
of this comes about because physicians eventually report it in their
meetings. But if there was a device
tracking, and registry maintained by manufacturers, or by the guidance, I'm not
saying industry has to necessarily do it.
Then
I think we would have noticed at a much earlier stage in the process, problems,
and prevented those problems from continuing to replicate themselves.
MS.
MAHER: So then I would guess it is your
opinion that all implants should be tracked?
DR.
CHENG: That is correct.
MS.
MAHER: So it is not specifically
relevant to cages, it is just all implants?
DR.
CHENG: Right.
CHAIR
YASZEMSKI: I would say through this
discussion a great part of the value of what happens here is the discussion
that FDA hears. They hear both sides of
it, and then they will act based upon the pros and cons that are put before
them.
For
purposes here I'm going to make a suggestion which we, of course, will vote on,
and all the voting members will get a vote.
But I'm going to make a suggestion that I'm hearing that we should check
device tracking, on number 7, we should check testing guidelines.
I
will suggest that we check the guidance document, and not performance
standards, based upon the discussion and clarification that Dr. Witten has
given us, and that we include those things we wanted to put in performance standards, in guidance document. And then we move on to number 8. I also note that the study of the retrieved
devices, if we include it, will have to go under other. And I think that I would like to ask Dr. Li
how -- we want to be careful that we do everything that must be done to make it
safe and effective.
But
also look at the other side which may be that it may be practically difficult
to get retrieved devices back to the company.
I would like to hear your thoughts as to whether perhaps we could put
study of retrieved devices as a recommendation under testing guidelines, or
should put it as a separate requirement that we would ask FDA to implement
under other.
Dr.
Li, your thoughts, pluses and minuses on that?
DR.
LI: Let me answer the practicality
question first, because I think it is a good one. Our lab, when I was in special surgery, and continue now, has
been doing retrieved implants for 15 years.
In
special surgery we collected over 10,000 devices, over that period of
time. And my experience is retrieval
analysis is as successful as you work at it.
So
if you actually establish a program for retrieved devices, in fact surgeons we
found are more than glad to send us all their retrieve devices. As far as what companies can do, there is
one company in the breast implant business, that actually gives you a rebate on
a revision.
So,
in other words, if you -- if someone comes in with a damaged breast implant,
and they need a revision, if you send in the one that was broken, if will, they will actually give the hospital,
or the surgeon, a rebate on the device.
Now,
I'm not suggesting that this be done here.
But I am suggesting that the retrieval analysis is as successful as you
want it to be. So I think from a
practical standpoint the details could be worked out, either with the company,
or with an independent lab, or independent hospitals, I think that can be done.
And,
again, I don't think you need tens or thousands to get a good picture on
performance. Now, as far as where you
put it, under testing guidelines, or as other, I'm not sure I understand the
real difference.
CHAIR
YASZEMSKI: I'm not sure it matters,
either. And I was going to suggest,
just for ease of putting things together, that we include it as one of the
testing guidelines.
DR.
LI: I have no problem with that, if
there is no difference.
CHAIR
YASZEMSKI: Okay. I will include among testing guidelines we
are going to suggest, as part of the vote, to include analysis of retrieved
specimens. Ms. Shulman, may we move on
to number 8?
MS.
SHULMAN: Did you want to vote on number
7, that that is what everyone agreed upon?
CHAIR
YASZEMSKI: Okay. I will ask it this way. Are there any concerns raised by anybody
that we do something other than check guidance document, device tracking, and
testing guidelines, to include study of retrieved devices under number 7? Dr. Larntz.
DR.
LARNTZ: I just want to clarify, on the
analysis of retrieved devices, this has to come after approval? I mean, this is a post-market, post-approval requirement for these devices?
CHAIR
YASZEMSKI: Dr. Witten, I'm not sure I
know how to answer that. Can I get your
interpretation of that question?
DR.
WITTEN: Well, I think your
recommendation could be whatever you recommend. But if you leave it open then
probably one of the things we would explore would be if it fits under our
discretionary post-market surveillance program, which is mostly for studies.
I
don't know that we have ever done this.
But -- or you could make a recommendation that people study these, and
do this prior to market. I'm not sure
exactly how they would do that, though.
CHAIR
YASZEMSKI: And, again, I will remind
all of us that what we vote on is not binding on FDA, and they need to hear
both sides of any arguments for the things that we vote on.
And
at the end, when we have a completed document, and we vote on that document,
regardless of what the vote is, whether it is unanimous one way or the other,
or whether it is split, we will go around the table and ask everybody to
explain why they voted the way they did, and that message does get to FDA as
they make their decisions with the companies.
Dr. Li?
DR.
LI: I'd like to explain, this is what I
had in my mind for the purpose of the retrieval analysis, is that I think that
one of the shortcomings, if you will, in this product is that there is no long
term data.
In
other words, the longest term data of any kind of significance is about two
years. And we have a smattering of data
out maybe to four years. So we don't
really know what the long term performance is in any kind of organized study.
So
the retrieval analysis, in my own conscience, is a way that I could essentially
make myself feel better that, in fact, things are not going in the worse
possible way, and they would validate the excellent performance that we seem to
be getting for the current devices, and it also establishes a baseline for
future devices.
So
that is my reason for doing the retrieval analysis. I had not intended it to be a pre-approval condition.
MS.
MAHER: Had you intended it to be for
the life of the product, forever more the companies must get these back and do
an analysis? Because I think that is
what --
DR.
LI: No, I think --
MS.
MAHER: -- very overburdensome. The other thing I would question is, you say
we don't have much history. But, again, these are very, very similar to
vertebral body replacement devices, and there is a fairly long history of those
being out there.
So
I would say that there is actually more of a history than we are actually
alleging. But that being said I think
we need to make it clear to the FDA, if you are talking about this retrieval,
that it is a limited number for a limited time, not forever and always, once
you have this device in the market you must try to get every device back,
because that would be impossible.
DR.
LI: Well, I'm not sure about the
impossible part but it wasn't -- it was not my intent to add a burden for the
company to follow all these devices forever.
And I think our history in studying retrieved analysis actually says
that you don't have to do that to determine the failure mechanisms and modes of
these devices.
In
other words, as time goes on you are going to get devices that come back after
a couple of weeks because of infection, and you are going to get some that come
in after, maybe, twenty years after an autopsy retrieval.
So
you are going to get in a retrieval collection a span of devices, just as a
natural course of collecting retrieved devices. And I think it will, in our past history, it has shaken out very
reasonably quickly what the failure modes are after that.
And
I think independent labs may be actually, like ours, are in a position to
continually gather these and study these forever, where I would not burden the
company to do so.
CHAIR
YASZEMSKI: Dr. Diaz, please go ahead.
DR.
DIAZ: I think if we include device
tracking it has to be also in a very limited time span. If we assume that the
device is intended for the facilitation of the completion of a fusion, and that
fusion has taken place in the lapse of six to nine months, there is no need to
continue tracking these devices for eternity when, in reality, their useful
life has, in fact, expired.
So
if the device fails, as Dr. Li indicated then, for sure, you need to know what
thing is doing, and if you get it out, get it out and check it. But if the patient has had a successful
fusion, I think it is onerous on anyone, be it the companies, the government,
the physician, or anybody, to keep track of these things forever.
CHAIR
YASZEMSKI: Dr. Cheng?
DR.
CHENG: Just two points to address your
inmediate concern, Dr. Diaz. I'm a
tumor surgeon, and the oncologic potential for materials is not realized within
just a couple of years. So there are
some long term effects that device tracking would be helpful to know about.
The
second point is I think we have to be a little bit careful in our comparison to
vertebral body devices. While there are
some parallels, as has been pointed out, by several individuals in the Panel
and in the audience, the experience I think is a rather -- the number of
procedures of vertebral body replacements is very small fraction, compared to
those undergoing disc surgery.
So
the ability of that to state that it is useful to compare it vertebral disc
replacement is rather limited.
CHAIR
YASZEMSKI: Thanks, Dr. Cheng. Dr. Finnegan?
DR.
FINNEGAN: I would like to follow-up on
that because the vertebral body replacements, as I understand it, are Class II
because they are pre-eminent materials.
And I would be willing to bet that if they actually had to go through
the present day process they would not be a Class II, they might actually even
be an HDE.
So
I think that to compare the two is actually mistaken.
CHAIR
YASZEMSKI: Thanks, Dr. Finnegan. Dr. Diaz?
DR.
DIAZ: My concern with the issue of the
potential oncogenic capacity of the materials I think has already been
addressed in other devices that have been studied with comparable material
structures.
I
think we would be trying to reinvent the wheel to check to see whether titanium
alloy, or carbon fiber, or PEEK, have a potential oncogenic ability if that has
already been evaluated, assessed, and checked for other devices.
So
I still go back to my idea of limiting the evaluation only to the time on which
the device accomplishes a fusion or doesn't.
CHAIR
YASZEMSKI: Other discussion?
(No
response.)
CHAIR
YASZEMSKI: For purposes of this I will
read this again, and recognize everybody is going to get a chance to vote. We are not voting that this is going to go
to FDA, we are going to agree how to fill this sheet out.
And
we are all going to look at the sheet at the end, and we are going to vote yes
or no on the sheet. And if anyone, for
example, likes most things on the sheet, but disagrees with one or two, they
can vote no, and transmit the message to the FDA that I voted no because of
number 6, or number 7, etcetera.
And,
again, one of the important things, in addition to the outcome of the vote, are
the reasons for voting, and that the FDA gets the messages for and against each
one of these components.
Having
said that I'm going to propose that we fill out number 7 with a check and
guidance document, with a check and device tracking, and include Dr. Diaz'
limited time span, that we can vary and in a generic sense say, until fusion
occurs.
And
check testing guidelines, and include in that retrieval analysis. Does anybody dissent to filling out the
sheet like this for number 7, upon which we will subsequently vote?
(No
response.)
CHAIR
YASZEMSKI: Ms. Shulman, number 8.
MS.
SHULMAN: Number 8 and number 9 we get
to skip because that only has to do with performance standards. Number 10 we can skip because that is only
for a Class III device.
So
on the second page, number 11, identify the needed restrictions. The first one is the basic restriction
legend. And then the others are on top
of that, use only by persons with specific training, or experienced in its use,
only in certain facilities, or other.
CHAIR
YASZEMSKI: Let's start this thing with
Dr. Diaz, if we can. And would you
suggest we check any, and if so, which ones?
DR.
DIAZ: I think for sure the box on the
use only by persons with specific training or experience is a necessity. I can see, for the various reasons that were
presented earlier, that we could allow people without training to make use of
them.
I
am torn, a little bit, with the box that follows, the use only in certain
facilities. We could follow the
suggestion made earlier, that these things are being used only in centers where
people with specialized training reside, and where the experience exists.
But
some of these individuals may move away to other facilities where if they,
themselves are performing it, in essence the capacity to do it is already
existent there, since they have just relocated.
So
my suggestion would be to only check the one box.
CHAIR
YASZEMSKI: Okay, thank you, Dr. Naidu?
DR.
NAIDU: I agree. I'm not sure the first -- I mean, I would
assume that persons with specific training or experience would also be lawfully
licensed practitioners, so I don't know what the first one is, the first box is
meant to do.
But
I do agree that use by persons with specific training experience in its use
should be sufficient.
CHAIR
YASZEMSKI: Thank you. Dr. Larntz?
DR.
LARNTZ: Use only by persons with
specific training and experience in its use.
CHAIR
YASZEMSKI: Since we are filling out the
sheet now, I ask for a point of order, if I might. I would like to hear whether Ms. Wells and Ms. Maher have
anything to suggest to this sheet. May
we do that, since we are not voting right now?
And
if that is okay I will ask Ms. Wells for suggestions.
MS.
WELLS: I don't have any additional.
CHAIR
YASZEMSKI: Thank you. Ms. Maher?
MS.
MAHER: I actually would have voted to
have it on written or oral authorization from practitioner licensed by law,
because I think that in your medical school training now people are adequately
trained on these already, on how to use them.
And,
therefore, we would be taking care of them, we could have discussion earlier
about surgeons training surgeons. And I
think going to that next step down adds a little bit of extra bells and
whistles that I'm not sure necessarily needs to be there.
CHAIR
YASZEMSKI: Thank you. Dr. Cheng?
DR.
CHENG: I will check the first two
boxes. Dr. Finnegan?
DR.
FINNEGAN: The first two boxes.
CHAIR
YASZEMSKI: Dr. Li?
DR.
LI: I will defer to my surgical
colleagues.
CHAIR
YASZEMSKI: I think that I will now ask,
since we've had some suggestions for checking the first box, some for checking
the second, and some for checking both, I will ask if it would be acceptable to
everyone if we check both? I don't see
anything to be lost by checking both.
And,
again, FDA will get our message during the discussion. So if there are no persons who would be
against that, we will check the first two boxes for number 11, and move on to
the supplemental data sheet.
MS.
SHULMAN: The supplemental data sheet is
designed to provide a device description, intended use, risk to the device, the
recommended class, and the scientific support for the class, and proposed level
of controls.
So
with that the first is generic type of device, the advisory panel, device and
implant, so we can go through those.
Number four indications for use.
You are welcome to say as was presented in the overheads, on the slides,
unless you had any changes to that.
CHAIR
YASZEMSKI: Okay. Well, let's do this. Rather than go around
to everybody, let's start with the recommendation for as presented in the
overhead, and open it up to anyone who wants to add or subtract from that.
Do
we have that overhead from before, is that something that is easily
retrievable, so that everyone can look at it?
It is in the package, okay. And
we've had a fairly thorough discussion.
I think if anyone would like to suggest either deleting or adding to
what we've seen and discussed today, as indications for use, please so
identify.
Otherwise
I'm going to propose that we take Ms. Shulman's suggestion and list, for number
four, as described in the presentation.
(No
response.)
CHAIR
YASZEMSKI: Hearing none, let's move to
number 5.
MS.
SHULMAN: Number 5, the identification
of any risks to health presented by the device. We can also go with what was presented in the overheads today, or
you can have any additions that you may want.
CHAIR
YASZEMSKI: When we discussed the
questions to FDA, what we discussed about health risks, were those that
were presented in the device, and then
we had, for a recap, a discussion of potential long-term risk at adjacent
segment disease, that seemed to be resolved by noting that once the fusion was
solid, that this probably was more dependent upon the change of local
mechanical properties of the functional spinal unit after fusion, than by any
of the properties of the material, per se.
And
the second thing that we asked was to emphasize the importance of the surgeon
and her or his education and training.
If there are additions to that, please let's entertain them now,
otherwise we will also fill number five out with as presented.
(No
response.)
CHAIR
YASZEMSKI: I will do that for number 5.
MS.
SHULMAN: Number 6, the recommended
advisory panel classification and priority.
The classification from the first page is Class II, and the priority
that you would vote on would be high, medium, and low. And that would be how fast do you want us to
go back and work on this reclassification, is it a top priority, medium?
Of
course there are no time frames associated with high, medium, or low.
CHAIR
YASZEMSKI: We, of course, are going to
vote. But having gone through the first sheet and with an aim at a potential
motion for Class II, I'm going to suggest that at the moment we put Class II in
here, and then we will entertain discussion about it and, of course, vote on
it.
But
the priority, may I hear, if we fill in Class II for the certification that we
will vote on, let me hear about the priority.
Dr. Diaz?
DR.
DIAZ: Since we know that the guidance
can move at a glacial pace, in many things, and there is no time commitment to
high, medium, or low, why don't we just put high and let the process evolve as
it will?
CHAIR
YASZEMSKI: And we will -- if there are
no objections, we will put high. Number
7, Ms. Shulman?
MS.
SHULMAN: If the devices and implant are
life sustaining, and life supporting, and has been classified in a category
other than Class III, explain fully the reasons for the lower classification,
with the supporting documentation and data.
And
just as a suggestion here you can say that the general and special controls can
handle the risks, or unreasonable risks, or you can put as was discussed today
in the Panel meeting.
CHAIR
YASZEMSKI: And perhaps I might suggest
that the discussion that led to our filling out the device questionnaire in
number 7 will suffice, and be part of as discussed in the Panel meeting.
We
have just gone through filling out about the guidance document, device
tracking, and testing guidelines. So
unless there are, again, objections I will suggest that for number 7, general
special controls with the additional recommendations as presented and discussed
at the Panel will be our answer to number 7.
MS.
SHULMAN: Number 8, summary of
information including clinical experience or judgement upon which
classification recommendation is based.
And once again you can say the information presented today.
CHAIR
YASZEMSKI: I will so move that we do
that, and ask if there are objections?
(No
response.)
CHAIR
YASZEMSKI: Seeing none, let's move on.
MS.
SHULMAN: Number 9, the identification
of any needed restrictions on the use of the device. We can refer to question 11 of the general questionnaire we
already had the specific training and all.
And you can add any others here.
CHAIR
YASZEMSKI: Again, I will suggest that
we refer to question 11, and ask if there are objections to not adding anything
else?
(No
response.)
CHAIR
YASZEMSKI: Seeing none, let's move on.
MS.
SHULMAN: Number 10 we will skip,
because that is a Class I question.
Number 11, if the device is recommended for Class II, recommend whether
FDA should exempt it from pre-market notification.
CHAIR
YASZEMSKI: Can you clarify for us so we
understand what we are saying, by exempt and non-exempt?
MS.
SHULMAN: That if there is not exempt,
if there is an exempt then no one would have to submit a 510(k) for these
devices.
CHAIR
YASZEMSKI: And if it is not exempt,
they would have to meet a 510(k) pathway?
MS.
SHULMAN: Yes.
CHAIR
YASZEMSKI: DO I hear a recommendation
for non-exempt. Are there any
objections to that?
(No
response.)
CHAIR
YASZEMSKI: Seeing none we will fill
number 11 out as non-exempt. Number 12?
MS.
SHULMAN: Any existing standards
applicable to the device, device subassemblies, or device materials. The standard reference could be standards
directed by professional groups, standards groups, or manufacturer.
CHAIR
YASZEMSKI: Dr. Finnegan?
DR.
FINNEGAN: Is this where we could bring
in our concern about the difference between metal and non metal?
CHAIR
YASZEMSKI: Ms. Shulman, would that be
appropriate?
MS.
SHULMAN: Yes.
CHAIR
YASZEMSKI: How should we state
this? Dr. Naidu, suggestions as to how
we might communicate our concerns regarding the nature of the material
composition in number 12?
DR.
NAIDU: I think we have discussed this in
detail. I mean, I think the most
important thing is that polymeric materials are inherently different from
metallic components, especially in this manufacturing methods.
There
can be great variations in this, and therefore specific testing that we recommend,
such as fracture toughness, and after the component fractures, the wear
particles that were generated from fracture components, and I think those need
to be delineated.
CHAIR
YASZEMSKI: I might -- if I may make a
suggestion? Since there is a transcript
of everything that we said, this entire discussion will be on the
transcript. And if we can refer to that
transcript in our concerns, regarding the wear, the particulate debris, the
fracture, etcetera, as have all been discussed, would it be appropriate to
refer to the Panel transcript, the discussion that we've had regarding material
properties as we answer number 12, here?
MS.
SHULMAN: That is fine.
CHAIR
YASZEMSKI: Would that satisfy you?
DR.
NAIDU: And in addition lack of clinical
data. That is the only other thing that
I would like to add, adequate clinical data for the polymeric material, that is
the only other issue that I'm concerned with.
CHAIR
YASZEMSKI: Objections?
(No
response.)
CHAIR
YASZEMSKI: I'm not certain how to pull
this. I'm looking at number 12 and it
speaks existing standards applicable.
And I'm not certain how we would communicate lack of clinical data to
FDA under number 12, although that communication will be clear from the
discussion we had.
DR.
WITTEN: And number 10 is really asking
what existing standards are applicable to the device.
CHAIR
YASZEMSKI: Number 10? Number 12.
DR.
WITTEN: We are on 12. Did I say
10? I meant 12. Number 12 is asking for existing standards
that are applicable to the device. So
it is asking, you know, when we talked about these special controls, are there
some specific standards that should be part of the special controls. That is what that is asking.
CHAIR
YASZEMSKI: I will ask if any of the
Panel feels that there are standards. I
guess my thought would be that we haven't discussed specific standards, we have
discussed specific concerns, which will of course be transmitted to FDA.
Dr.
Li, may I ask your commentary on that?
I think the concerns are going to be well transmitted to FDA. And I guess this question is asking whether,
perhaps like ISO or ASTM standards that we are aware of. And I don't believe that we discussed any of
those.
DR.
WITTEN: Well, we referenced some of
them in our presentation.
MS.
MAHER: There were a lot of them
reference --
CHAIR
YASZEMSKI: Can we, would it be
appropriate, then, to reference the standards that were in the presentations
that were made today, and the discussion that followed regarding them?
MS.
SHULMAN: Yes. And if you want to amend the general device classification
questionnaire number 7 about the clinical data question, and what you just
brought up, that will be in the record for that, for the special controls.
CHAIR
YASZEMSKI: Okay, that would be good. And that will be under the guidance
document, of number 7?
MS.
SHULMAN: Correct.
CHAIR
YASZEMSKI: Does that satisfy you, Dr.
Naidu, to put the concern regarding clinical data under the guidance document,
number 7, on the general device questionnaire?
DR.
NAIDU: Yes, thank you.
CHAIR
YASZEMSKI: And for number 12, on the
supplemental sheet we will refer to the standards that occurred in the
presentations today, and the discussion regarding those standards that
followed. Dr. Li?
DR.
LI: Again, I'm not sure we are going to
be redundant. So are you asking for --
I guess my issue is there are some tests that I would like to see done that
weren't presented on your list, because --
MS.
SHULMAN: This is where you would list
them.
CHAIR
YASZEMSKI: I think the way I'm reading
this, and I will ask Ms. Shulman and Dr. Witten if I'm reading this
incorrectly. For number 12 we would put existing standards.
And
I would think that if the test you are referring to, our tests that have an
ASTM or ISO standard, yes, they go here.
If they are not, then they would go under testing guidelines, in number
7, under general device classification sheet.
DR.
LI: I understand.
CHAIR
YASZEMSKI: Which are they?
DR.
LI: Well, I was thinking of things that
have ASTM or ISO guidelines existing.
CHAIR
YASZEMSKI: Okay. I'm not going to ask
you to remember the numbers now, but if in general you can say what the tests
are, we can attach the numbers to them later.
What tests did you have in mind?
DR.
LI: There is an ASTM and ISO standard
for fracture toughness testing, mainly typically use a J or a K test, but
typically for medical devices the sample requirements for K tests are too
large, so J tests are typically used, when they are used for factory toughness
testing.
There
are also, none of -- your standard on PEEK is for neat PEEK, and the absence of
fibers. But there are ASTM and ISO
standards for composite materials and devices, and their subsequent testing.
So
I would look, there are a bunch of those, I would have to go back and look
specifically to see which would be appropriate for this particular
application. But there are existing
tests that define composite makeups and how you subsequently test them for
fracture and fatigue, which are not covered by the list that you provided us so
far.
CHAIR
YASZEMSKI: Dr. Witten, would it be
acceptable to FDA if we noted not the specifics tests, but that these are tests
on fracture toughness and composite device, mechanical properties that we will
supply the actual ASTM ISO numbers at a later time.
For
purposes of this sheet, would this suffice?
DR.
WITTEN: Yes.
CHAIR
YASZEMSKI: Thank you. Next, Ms. Shulman?
MS.
SHULMAN: So the last thing left would
be to just vote on the sheets.
CHAIR
YASZEMSKI: So if I -- we will have to
vote, first, that we agree on the sheets. I think we have done it on a point by
point basis. But I will review the
answers and then ask everybody to vote yes or no, that they feel the sheet is
filled out appropriately.
Then
I'm going to ask Dr. Diaz for a motion.
So first let's look at the sheets.
The general device classification questionnaire, is it life sustaining
or life supporting? No.
Is
it for a use which is of substantial importance in preventing impairment of
human health? Yes. Does it present a potential, unreasonable
risk of illness or injury? No.
Number
4, yes. Number 6, is there sufficient
information to establish special controls, in addition to general controls, to
provide reasonable assurance of safety and effectiveness? Yes.
Number
7, if there is sufficient information to establish special controls to provide
reasonable assurance of safety and effectiveness, identify them below.
We
have checked guidance document, which will include the request for clinical
data. We have checked device tracking,
and stated that we feel it is for a limited time span, until fusion occurs.
We
checked testing guidelines, which will include fracture toughness testing, and
retrieval analysis in addition to tests that have been done for the devices
that have already been approved throughout the PMA pathway.
We
moved -- actually, I have to step back.
The reason I'm hesitating is that I don't see that we answered number
9. Did we, and did I miss it? For device recommended for certification
into Class II, should the recommended regulatory performance standards --
excuse me, it is for performance standards only, excuse me. So we skip 8, 9, and 10, pardon me.
Eleven,
identify the needed restrictions. We
checked the first two, only upon the written or oral authority of a
practitioner licensed by law to administer and use the device.
And
the second one, use only by persons with specific training or experience in its
use. Moving to the supplemental data
sheet, the indications for use in device's labeling. We are going to say as
described in the presentations today.
Number
five, identification of any risks to health presented by device, as described
in the presentations today. Number 6,
recommended classification and priority, Class II priority high.
Number
7, we stated that general and specific controls with recommendations as
discussed at the Panel today. Number 8,
a summary of information including clinical experience, as discussed at the
Panel meeting today.
Number
9, identify an identification of any needed restrictions on the use of the
device, as discussed in number 11, on the general device classification
questionnaire.
Number
10 is not applicable. Number 11, if
device is recommended, recommend whether it should be exempt from pre-market
notification. We checked not
exempt. Number 12, are there existing
standards applicable to the device?
We
are going to ask for fracture toughness standards, and composite device
material property standards, that we will supply the specific numbers for, from
ASTM and ISO, at a later time.
I'm
going to go around and ask for a vote as to whether these sheets are filled out
to your satisfaction. May I ask for a
point of clarification? We are voting
now just to say that everybody agrees that the sheets are appropriate?
Maybe
I should say it this way. Since we've
been through this, are there any objections to the sheets, as I've written
them? Dr. Finnegan.
DR.
FINNEGAN: Just a point of order. On number 5, for the supplemental data
sheet, did you not want to say as discussed?
Because the discussion was a little bit more than as described.
CHAIR
YASZEMSKI: Yes, as discussed at the
Panel meeting. Thank you, Dr.
Finnegan. Other comments? Dr. Li?
DR.
LI: Just to -- I'm not sure I need to
add this, but as far as in section 12 of the supplemental data sheet, I was
wondering if the FDA could reexamine what worse case scenario is in the
testing.
Because
a lot of the testing that is described in the guidelines we provided, that they
would be tested in the worse case scenario.
But then looking at the actual test I don't believe there are actually
what I would consider the worse case.
So
it would be -- it really is an amendment to the guideline, other than to
reevaluate what they are going to accept as the worse case.
CHAIR
YASZEMSKI: May I suggest that since 12
is asking for existing standards, that we put our recommendations regarding
reassessment of the worse case into number 7 from the general device
certification questionnaire under testing guidelines?
DR.
LI: That would be fine.
CHAIR
YASZEMSKI: And then we can make
language that suggests that they do just that, based on the discussion we are
having now.
DR.
LI: That would be fine.
CHAIR
YASZEMSKI: Dr. Cheng?
DR.
CHENG: Well, my only quibble is this
device tracking thing. You know, this
is not onerous on the people we are asking.
Basically you hook the patient, getting the patient's Social Security
number who is getting a device, to the tag number for the device, and that is
it.
And
whether they keep it for two years until fusion occurs, or 20 years, is not
going to make a big difference. But you
need to have the information. If you
don't have the information, then you don't have it. So I don't think there needs to be a time limit.
DR.
DIAZ: Well, my concern with that
concept is that it does not really limit itself to the acquisition of the
Social Security number and name, rank, and serial number, but it requires some
form of monitoring.
And
that form of monitoring can be as simple as an annual letter from the patient
saying, hello, how are you, Merry Christmas, or something like that. Or to a very intrusive evaluation of the
patient, including radiographic testing, biomechanical studies of spine,
etcetera, etcetera, etcetera.
I
mean there is no definition, there is no limit on that.
MS.
MAHER: And, actually device tracking
really just means that the manufacturer is required to track where the patient
lives at all times. And I can actually
tell you, from experience, I run a patient registry, and we've got three years,
almost four years worth of data into it.
And
it is a fairly simple registry, I send them a form every year. And they respond, and when they respond I
send them a check for 25 dollars. You
would think that these people would want to stay informed, because it is a two
page form that they get to fill out, they get a 25 dollar check.
Quite
honestly each year the number goes down of people who are even interested in
allowing me to voluntarily track where they are, and follow that with
them. Now, in this case when you
mandate device tracking, you are mandating that we, the manufacturer, keep
track of where these patients are, for the rest of their lives.
Because
that is really what the device tacking regulation does. And I honestly don't see where that brings
anything, any benefit, necessarily, to the companies, or to the industry, or to
you all.
That
provision was originally put in place when the Shiley heart valves
fractured. And part of it was because
it was so hard to find out who had Shiley heart valves to begin with, to tell
them they should come back in and get it replaced.
So
that is where it is looking, how you can quickly get a hold of these people, to
tell them there is a problem, to tell them to come back in and get it
replaced. These patients will have had
their backs fused, but hopefully the spine will have fused, the cage will be
fused in there, or are you going to be taking this out? What is the benefit for being able to know
that Sally Maher had a spinal cage put in her back 20 years ago, and it is
still walking around fine?
I
mean, you wouldn't be sending me forms to find out if I'm walking around fine,
you just would know where I live to be able to find me.
CHAIR
YASZEMSKI: Thank you. May I ask, Dr. Witten, you counseled us
before --
DR.
CHENG: Could I respond to that?
CHAIR
YASZEMSKI: Go ahead, Dr. Cheng.
DR.
CHENG: I run patient clinical studies
as well, there is no question it is difficult to get people to respond to you,
and that is not what I'm advocating here.
If
you tag this to the patient's Social Security, then the federal government
knows where you are.
MS.
MAHER: We are not allowed to use Social
Security numbers.
DR.
CHENG: Well, that is a different issue
for the FDA to deal with, okay?
MS.
MAHER: We can't use the Social Security
number.
DR.
CHENG: That is a fact. Then you don't have to do it, let the FDA do
it. What I'm saying, the principle of
tracking devices is important. Despite
the hissing in the audience, no one knows the incidence of oncologic tumor
development after prosthetic device.
It
is low, I'm not denying that, okay, and I don't think it is a major issue. But I'm just saying if my mother is going to
undergo a cervical cage, and five people have become myopathic because of an
osteolysis from a cervical cage, three years after fusion, I want to know about
it.
And
no one is going to know about it, unless you keep track. There is no way you
are going to know anything, unless you keep track of the information.
MS.
MAHER: Then I think we need to go to
Congress and have them change the law.
DR.
CHENG: That is not a problem. I mean, that is a problem, but that is a
different issue, and the FDA will have to address that. But the recommendation for this panel is, at
least that I'm trying to propose, is that it is important for us to keep track
of information.
MS.
MAHER: So, again, you are proposing
that the FDA track all implants, not just final cages?
DR.
CHENG: Sally that is what I said, yes.
CHAIR
YASZEMSKI: May I ask, Dr. Witten, you
mentioned to us before that performance standards have been used incredibly
infrequently. What is the frequency with which device tracking is used?
DR.
WITTEN: There are a few tracked
devices. I can't tell you what they are
-- how many? There are two to five. The only one in our division are dura mater
allografts, which are treated as medical devices.
So
it is not very frequent.
CHAIR
YASZEMSKI: It is very infrequent.
DR.
WITTEN: And let me just say that, I
think just for clarification to us, FDA, to FDA, which is I think that the term
tracking in our regulations, in our minds, is what Ms. Maher mentioned, which
is being able to locate the patient.
It
doesn't include any kind of data collection, it is just being able to locate
the patient if there is something that happened with the product that makes you
want to go back and discuss it further with the recipients.
CHAIR
YASZEMSKI: Recognizing that, and
recognizing, also, Dr. Cheng's plea, which is that we should know where these
things are, and that you folks will consider both the pluses and minuses when
we make our recommendation to you, I'm going to propose that unless there are
objections we leave it as it is, we will leave it checked, and you can act upon
it as you see fit.
So
if there are no objections I'm going to state that we are in agreement that the
sheets are filled out to the satisfaction of all of us, to be presented now to
vote upon in a motion.
And
I'm going to ask if Dr. Diaz would make a motion?
DR.
DIAZ: Yes, Mr. Chairman. I would like to move that that the Panel for
Orthopedic and Rehabilitation Devices accept the reclassification of the
Intervertebral Body Fusion Devices from Class III to Class II, following the
described guidelines that we discussed in the General Device Classification
Questionnaire, and complemented by the Supplemental Data sheet.
CHAIR
YASZEMSKI: Thank you. Do I have a second?
DR.
FINNEGAN: Second.
DR.
LARNTZ: Second.
CHAIR
YASZEMSKI: Dr. Finnegan has seconded
it, we have a third. We have had quite
a bit of discussion. If anyone has
additional things that they would like to add at this point, I will open it up
and ask for further comments.
But
if there are none I'm going to state that we are ready for a vote. And what we will then do is I will ask for a
restatement of the motion, either by Dr. Diaz or by me, and I will start going
around the room.
Now,
this time I'm going to start, when we do vote, I will start with Dr. Naidu, we
will record the vote. So not seeing any
further discussion, may I ask you, Dr. Diaz, just say it one more time, and as
soon as you are done saying it we are going to ask for a yes or no, or an
abstention from everyone, starting with Dr. Naidu, and moving clockwise.
DR.
DIAZ: I don't know if I can say it
verbatim the same, but I will try. I
would like to move that the Panel for Orthopedic and Rehabilitation Devices
approve the reclassification of the Intervertebral Body Fusion Devices, known
as cages, from Class III to Class II, based on the description that we have
outlined pm the General Device Classification Questionnaire, and complemented
by the Supplemental Data sheet.
CHAIR
YASZEMSKI: Thank you. Dr. Naidu?
DR.
NAIDU: Yes.
CHAIR
YASZEMSKI: Dr. Larntz?
DR.
LARNTZ: Yes.
CHAIR
YASZEMSKI: Dr. Cheng?
DR.
CHENG: Yes.
CHAIR
YASZEMSKI: Dr. Finnegan?
DR.
FINNEGAN: Yes.
CHAIR
YASZEMSKI: Dr. Li?
DR.
LI: Yes.
CHAIR
YASZEMSKI: Dr. Diaz?
DR.
DIAZ: Yes.
CHAIR
YASZEMSKI: The motion has carried
unanimously. It is the recommendation
to the Panel, to the FDA, that the intervertebral body fusion devices be
reclassified into Class II, with the guidance document, and the other
recommendations as presented in the supplemental data sheet and the general
device classification questionnaire.
I'm
going to ask now each panel voting member an opportunity, give an opportunity,
regarding the reason for his or her vote.
Then I'm going to ask, after that is done, the consumer representative,
and the industry representative, if they would like to make any comments.
Dr.
Naidu, comments?
DR.
NAIDU: You know, I think I have stated
my opinions pretty clearly, previously.
And I don't have anything else to add.
CHAIR
YASZEMSKI: Thank you. Dr. Larntz?
DR.
LARNTZ: Yes, I certainly support this
reclassification. I do want to say one
last plea, when implementing the standards testing that care be taken in doing
the evaluation. I think Dr. Li was
saying maximum load.
I
think it can be done at various loads, and in fact the testing should be done
in a statistically valid fashion, as proposed in some of the standards.
CHAIR
YASZEMSKI: Thank you. Dr. Cheng?
DR.
CHENG: I have no further comments.
CHAIR
YASZEMSKI: Dr. Finnegan?
DR.
FINNEGAN: The only comments I would
make were in the supplemental document for number 4, I do think that the surgical instructions need to go to the surgeons
and are no longer necessary for the FDA.
And
I would really like to see allografts considered, although I understand that it
may not be part of what is presently available.
CHAIR
YASZEMSKI: Thank you, Dr.
Finnegan. Dr. Li?
DR.
LI: My only discomforts that I have
remaining are we are approving down classification on a specific device for
which we have actually very little long term data. However, on the other side of that coin, there is nothing in the
short term data that would lead me to believe that bad things are about to
come.
Which
actually then puts my worry in devices yet to come. Because there is, we have been fortunate, for some reason,
blessed with a very good success rate of these devices, but I don't think there
is complete understanding for why they are performing the way they are exists.
CHAIR
YASZEMSKI: Thank you, Dr. Li. Dr. Diaz?
DR.
DIAZ: My only additional comment is
just a restatement of what I said earlier, that I think that the applicability
of these devices needs to be broader, and not limited to very specific segments
of the spinal column, and that the use of the devices be approved, or allowed,
at multiple levels throughout the spine, with the appropriate devices is
designed for each space.
CHAIR
YASZEMSKI: Thank you, Dr. Diaz. Dr. Witten?
DR.
WITTEN: No, I think you were going to
ask for comments.
CHAIR
YASZEMSKI: Ms. Wells?
DR.
WITTEN: No comment.
DR.
TROMANHAUSER: Thanks very much. Ms.
Maher?
MS.
MAHER: I actually think that this is a
good decision, these devices clearly have no more risks than the other spinal
fusion devices that are currently on the market. Thank you.
CHAIR
YASZEMSKI: Thanks to everybody, I
appreciate the time and energy the Panel members have spent, and the FDA, I
appreciate your service. Thanks to the
FDA for preparation, and to the Petitioners, and to everyone who came today.
This
meeting of the Orthopedic and Rehabilitation Devices Panel is now adjourned.
(Whereupon,
at 2:12 p.m., the above entitled matter was concluded.)