UNITED STATES OF AMERICA
FOOD AND DRUG ADMINISTRATION
CENTER FOR DEVICES AND RADIOLOGICAL HEALTH
MEDICAL DEVICES ADVISORY COMMITTEE
GENERAL AND PLASTIC SURGERY DEVICES PANEL
+ + + +
+
64th MEETING
+ + + + +
FRIDAY,
NOVEMBER 21, 2003
+ + + + +
The panel met at 1:00 p.m. in the
Walker/Whetstone Rooms of the Gaithersburg
Holiday
Inn, Two Montgomery Village Avenue, Gaithersburg,
Maryland, DR. PHYLLIS CHANG, Acting Chairperson,
presiding.
PRESENT:
PHYLLIS CHANG, M.D. Acting Chairperson
GRACE T. BARTOO, Ph.D., R.A.C. Industry
Representative
BRENT A. BLUMENSTEIN, Ph.D. Voting Member
JOSEPH V. BOYKIN, JR., M.D. Temporary Voting
Member
ROBERT F. DIEGELMANN, Ph.D. Temporary Voting
Member
JOHN DOULL, Ph.D., M.D. Temporary Voting
Member
PRESENT (Continued):
LEE LEE DOYLE, Ph.D. Consumer
Representative
JOHN F. HALSEY, Ph.D. Temporary Voting
Member
JOSEPH LoCICERO III, M.D. Voting Member
MICHAEL J. MILLER, M.D. Voting Member
AMY E. NEWBURGER, M.D. Voting Member
MICHAEL J. OLDING, M.D. Temporary Voting
Member
ON BEHALF OF GENZYME CORPORATION:
JAMES BURNS, Ph.D. Sr. VP, Biomaterials
Research
FRANK DeLUSTRO, Ph.D. Global Biodevice
Development, LLC
LAURA FLEMING Associate Director,
Clinical Research
LENA HOLMDAHL, M.D., Ph.D. Sr. Director, Clinical
Research
WYTSKE KINGMA, M.D. Sr. VP,
Pharmacovigilance/
Medical Info
KAY LARHOLT, Sc.D. Sr. Director,
Biostatistics and
Statistical
Programming
GARY MONHEIT, M.D. University of
Alabama‑Birmingham
RICHARD POLISSON, M.D., MSHc Sr. VP, Clinical
Research
SUSAN RICHARDS, Ph.D. VP, Immunology
SUSAN STEWART VP, Regulatory Affairs
FDA REPRESENTATIVES:
DAVID KRAUSE, Ph.D.
HERBERT LERNER, M.D.
PHYLLIS SILVERMAN, M.S.
CELIA WITTEN, Ph.D., M.D.
I‑N‑D‑E‑X
AGENDA ITEM PAGE
Call to Order 5
Open Public Comments 7
Dr. Diana Zuckerman 7
Applicant Presentation, Genzyme Corporation, 13
Hylaform
Introduction 13
Sue Stewart, Vice President, Regulatory
Affairs
Preclinical Review 17
James W. Burns, Ph.D, Senior Vice President,
Biomaterials Research
Clinical Study Design 23
Richard P. Polisson, M.D., MSHc, Senior Vice
President, Clinical Research
Clinical Study Results 40
Lena Holmdahl, M.D., Ph.D., Senior Director,
Clinical
Research
Conclusion 56
Susan Stewart
FDA Presentation 89
Introduction and Clinical Review 89
Herbert Lerner, M.D.
Preclinical Review 90
David Krause, Ph.D.
Statistical Review 102
Phyllis Silverman, M.S.
Panel Deliberations and Address FDA
Questions 111
I‑N‑D‑E‑X
(Continued)
AGENDA ITEM (Continued) PAGE
Sponsor Summation, Concluding Panel 144
Deliberations and Vote
P‑R‑O‑C‑E‑E‑D‑I‑N‑G‑S
(1:35 p.m.)
CALL TO ORDER
EXECUTIVE SECRETARY KRAUSE: We
are ready
to begin the afternoon portion of the General and
Plastic Surgery Devices meeting. Before I turn the
meeting back over to Dr. Chang, I would just like
to
remind everybody here that you are requested to
sign
in on the attendance sheets, which are outside
the
door, if you didn't do so this morning.
Also, there is information out at that
table that is right outside the door, such as an
agenda or a roster of the panel. There is also
information regarding today's meeting. There is also
information out there that you can obtain on
methods
of finding out how to find out about future
meetings
and things like that.
Now that we all seem settled, I am going
to turn the meeting back over to Dr. Chang. Wait.
We
do have a public testimony session before you
start.
So could you just clear that table until the
public
testifiers are done? Thank you. I appreciate
that.
Okay. Now let's start the
afternoon and
go back to Dr. Chang. Thank you.
ACTING CHAIRPERSON CHANG: Good
afternoon.
We will now proceed with the next open public
hearing
session of this meeting. All persons addressing the
panel are asked to speak clearly into the microphone
as the transcriptionist is dependent on this
means of
providing an accurate record of this meeting.
As mentioned this morning, both the Food
and Drug Administration and public believe in a
transparent process for information gathering and
decision‑making to ensure such transparency
at the
open public hearing of the advisory committee
meeting.
FDA believes that it is important to
understand the context of an individual's
presentation.
For this reason, the FDA encourages
you, our public hearing speaker, at the beginning
of
your written or oral statement to advise the
committee
of any financial relationship that you may have
with
the sponsor; its product; and, if known, its
direct
competitors.
This may include sponsor's payment of
your travel, lodging, or other expenses in
connection
with your attendance at this meeting.
Likewise, FDA encourages you at the
beginning of your statement to advise the
committee if
you do not have such financial
relationships. If you
choose not to address this issue, it will not
preclude
you from speaking.
We have one individual who has notified
the FDA of their intent to testify during this
open
public session.
Is Dr. Diana Zuckerman or her
representative available to speak this afternoon?
OPEN PUBLIC COMMENTS
MS. SANTORO: Good
afternoon. My name is
Elizabeth Santoro. I'm a health policy fellow at the
National Center for Policy Research for Women and
Families.
I will be reading the testimony of our
president, Dr. Diana Zuckerman, who, regretfully,
could not be here today. Our center is a think tank
that translates scientific research findings into
meaningful information for the public. We use that
research information to advocate for policies
that
benefit the health and safety of children, women,
and
families.
We have several concerns about Hylaform.
As I stated at this morning's session, it
is difficult for us to testify before the data
are
presented.
We are basing this testimony on the
information that was made available on the FDA
Web
site yesterday.
Our concern about Hylaform is the
lack of data for African Americans and Asian
Americans.
Only three of the patients are African
American, and only five are Asian Americans.
Our concerns were addressed with the
National Medical Association and to the FDA
commissioner a few months ago. Research clearly shows
that African Americans are more likely to produce
keloids and can respond differently to procedures
involving the skin. In addition, African Americans
are more likely to develop autoimmune diseases
than
white women.
The company has not studied a reasonable
number of African Americans or Asian Americans to
approve the product for those populations.
It is not appropriate to require studies
of minority populations on a post‑market
basis since
the FDA does not have the authority to enforce
such
requirements.
The company should be required to do
the studies before the product is approved.
It is also inappropriate to label the
product "For whites only." This would be acceptable
if a product were found to be safe for whites but
unsafe for other racial or ethnic groups, but
such a
label is not an appropriate way around a
sponsor's
failure to conduct research on people of color.
And, of course, if the product were
approved, it would probably be used off label for
people of color. And that could potentially be
dangerous.
Research is needed. It won't
take long to
do it.
And it should be done.
We are also concerned about the sample
size. The
sample starts with only 133 people, and
only 123 are still in the study after 12
weeks. Since
this is a cosmetic procedure that is likely to be
used
by hundreds of thousands, perhaps millions of
people,
the product should be tested on a larger sample
to
determine if there are rare adverse reactions
that are
serious enough to consider before approval.
The study only lasted for 12 weeks, which
is a major concern. According to the FDA slides,
safety data, immunological responses were at four
weeks.
This obviously is too short a time to prove
whether this product is safe.
Since this product doesn't last long,
women would need to undergo the procedure
multiple
times. It
is clear from published reports that women
who have a good outcome the first or second time
they
use this product may have serious adverse
reactions
after the third or later procedure. This needs to be
studied before approval since it is clear that
their
product will be used more than once or twice.
The sponsor also excluded women who had
procedures in the previous six months. This is not
how the product will be used in the real
world. And,
again, it raises safety concerns.
A major shortcoming of this research is
the high adverse reaction rate. I don't consider this
necessarily a problem of the product but, rather,
of
the study design.
It is not helpful for the sponsor to
evaluate adverse reactions in a way that almost
all
the women using this product or Zyplast all have
adverse reactions.
The additions of serious or severe adverse
reactions is helpful, but it seems likely that
there
is a continuum of problems between what is listed
as
an adverse reaction, which almost everybody
experiences, and what is listed as a serious
adverse
reaction, which almost nobody experiences.
The standard needs to be set in a way that
is more meaningful. For example, it should measure
adverse reactions lasting more than a day or two.
That would enable the FDA to determine how safe
this
product is compared to other products.
I don't think the FDA should be approving
a cosmetic product where 88 percent of the
patients
have adverse reactions. Either the FDA should reject
this product or require the company to provide a
more
meaningful measure of adverse reactions.
In conclusion, I have even more concerns
about this product than about Restylane. According to
the company's own data, this product is not
necessarily better than the comparison product
Zyplast
and apparently may not last as long. For that reason,
I believe rushing this product to market without
gathering the additional data listed above is
unwarranted.
Thank you.
ACTING CHAIRPERSON CHANG: Thank
you.
Is there anyone from the general public
who wishes to make a public comment limited to
five
minutes?
(No response.)
ACTING CHAIRPERSON CHANG:
Hearing none,
we would like to at this time invite Genzyme
Corporation to present their PMA information.
APPLICANT PRESENTATION, GENZYME CORPORATION,
HYLAFORM
INTRODUCTION
MS. STEWART: Good afternoon, Dr.
Chang,
members of the panel and FDA. My name is Susan
Stewart.
I'm a vice president of regulatory affairs
at Genzyme Corporation. We are happy to be here today
to present Hylaform to you. And I would like to start
with a brief introduction and overview.
Dr. Burns will begin our
presentations
with a description of our device and a
presentation on
the preclinical studies in support of the safety
of
Hylaform.
Dr. Polisson will then summarize our
rationale, clinical history, and discuss and
describe
the study that we are later going to present
results
on with Dr. Holmdahl that shows we are comparable
to
Zyplast, the standard of care.
We also have with us a number of
colleagues and invited experts that are available
to
assist us in answering questions as they arise.
They're listed here on these two slides. I
specifically would like to point out that we have
with
us today principal investigator for the study Dr.
Ellen Gendler as well as Dr. Gary Monheit and Dr.
Leslie Baumann, also investigators in our study.
Now I would like to give some background
on Hylaform.
Hylaform is a clear, colorless hylan B
gel.
Hylan B is composed of cross‑linked HA, which is
a naturally occurring polysaccharide found in all
human tissue, including skin, and is found to be
identical across all species.
Hylan B used in Hylaform is also used in
our product Synvisc, which is a visco supplement
used
to treat osteoarthritis. We sold approximately nine
million doses of Synvisc around the world.
This is the indication that we are seeking
for Hylaform.
I would like to point out it is also
the indication for which we have been granted
approval
in about 30 countries around the world. I would like
to read it for you now, "Hylaform is
injected into the
mid to deep dermis for correction of soft tissue
contour deficiencies, such as wrinkles or acne
scars."
Outside the U.S., Hylaform is sold as a
product family.
They include Hylaform, Hylaform Plus,
and Hylaform Fineline. Hylan B is the main component
to these three products. The only difference in these
dermal fillers is that they have been processed
to
optimize delivery through a range of needle
sizes.
These were produced in reaction 2 position
preference
and surgical practice.
I would like to be clear that although the
subject of the PMA is Hylaform, we do refer to
Hylaform Plus later in the presentation. The
commercial history of Hylaform begins with our CE
mark
in 1995, which allowed us to begin launching
product
in all the European Union countries in 1996. Since
then, Hylaform has been used to treat a variety
of
wrinkles, including the nasolabial fold, those
around
the lip and periorbital areas.
No pre‑implant skin test has been required
when using this product. And we report a worldwide
overall post‑market adverse event rate of
about 0.1
percent.
This time line illustrates our current
status in the United States. Please note that the
sponsor of this PMA is Genzyme and that our
worldwide
marketing partner is Inamed Corporation.
Initial clinical studies in the U.S. were
conducted under an IDE sponsored by Biomatrix,
Incorporated of Ridgefield, New Jersey. Safety and
efficacy of Hylaform were evaluated in a 216‑patient
open label single arm study. A PMA was later
submitted, which was then withdrawn by Biomatrix
due
to issues concerning the clinical design. Please note
that this study did form the basis of our
approvals
outside the United States.
In 2000, Genzyme Corporation acquired
Biomatrix.
And by 2000, we had begun new studies with
Hylaform using a protocol that we believe
addressed
the issues raised in the original PMA.
Our PMA was then submitted and has been
reviewed as a modular PMA. We have been submitting
sections over the past year, with our final
clinical
module submitted in August of 2003.
Now I would like to ask Dr. Burns to begin
the preclinical presentation. Thank you.
DR. BURNS: Thank you and good
afternoon.
PRECLINICAL REVIEW
DR. BURNS: I am Jim Burns. I am senior
vice president for biomaterials research at
Genzyme.
I am going to provide some brief background on
Hylaform and a brief description of our
preclinical
studies that preceded the clinical trials that
you
will be hearing about.
As you have heard, Hylaform is a
hyaluronan‑based gel that is injected into
the dermal
tissue to provide space‑occupying
augmentation of the
extracellular matrix, thereby providing a
temporary
correction of skin contour deficiencies, such as
folds, wrinkles, as well as acne scars.
By the way, during this presentation and
subsequent presentations, you will hear
hyaluronate,
hyaluronic acid, hyaluronan. And for simplicity's
sake, we will very often just call it HA.
HA is particularly well‑suited for this
application of dermal augmentation because it is
already an important component of extracellular
matrix.
And within the extracellular matrix, it is in
a proteoglycan complex called aggrecan.
You can see on this slide the HA molecule,
which is a slender ribbon here, which is
associated
with protein as well as other glycocyamine
glycans,
chondroitin sulfate, and keratin sulfate. If you
looked at an electron micrograph of this complex,
you
would see a ribbon of HA that is decorated with
comb‑like structures shown here.
This structure is very important for wound
repair.
It is important for allowing cells to migrate
into a dermal wound. In this hylan‑rich milieu, it
also helps regulate the fluid retention. And it keeps
the tissue hydrated.
When it is not associated with this
proteoglycan complex, relatively dilute
solutions, it
can form fairly slippery or lubricous solutions,
such
as occur in synovial fluid for joint
protection. In
high concentrations, it will form a gel‑like
structure
that is useful for mechanical support to occupy
space
as in a vitreous humor of the eye.
Not surprisingly, it's found its way into
a number of products that are available in the
U.S. as
well as throughout the world. Here are some examples
of those.
HA is a primary component of a product for
adhesion prevention and gynecologic as well as
abdominal surgery. It's also in a class of products
shown here for prevention or dealing with the
pain of
osteoarthritis.
In this case, the viscoelastic solutions
are injected intra‑articularly in the
knee. They also
have found their way into viscoelastic solutions
that
are used in cataract and intraocular lens
surgery.
Actually, an important point of this slide
I want to point out is that HA is a very
interesting
molecule in the sense that it is biogenetically
conserved, that structurally and chemically, it
is
identical, whether it comes from the protective
cell
coat of a bacterium from an avian source or from
our
own synovial fluid. The differences among HA
preparations come from purification processes
from the
source, from low molecular weight or low‑level
contaminants or molecular weight of the HA.
So let me briefly describe some of the
design characteristics that we wanted to have in
a
dermal filler.
First, we want to balance durability
with safety.
Any biomaterial that you implant in the
body is going to elicit a reaction. And we wanted to
ensure that we could provide temporary
augmentation
without generating an untoward response.
So we feel we have done that with this
particular formulation. So our material provides
temporary correction and biorebsorbs with minimal
tissue reaction.
We feel that it possesses acceptable
viscoelastic properties so that it can withstand
some
of the forces that would be present at the site
of
injection that will remain at the injection site
for
an appropriate period of time and also be easily
injectable.
Natural HA will not meet these criteria
because it will resorb and clear from the site
fairly
quickly.
So we get to this product by starting with
avian tissue and treating that tissue in situ to
increase the molecular weight of the HA through a
formaldehyde treatment.
This is still water‑soluble HA of high
molecular weight of about four to six
million. We
then cross‑link that further to form a
gel. So we
have hylan A, which comes from the avian tissue
through out modification process, and then hylan
B gel
is the component that goes into Hylaform.
This is just going to illustrate the
cross‑linking with hyalanosulphone. So we see two
parallel chains of hyaluronic acid on the left in
yellow.
We see the basic monomeric unit of HA, which
is glucuronic acid or neutral pH sodium glucouron
and
acetyl glycocyamine. Under basic conditions and only
under basic conditions divinyl sulphone will
react
with free hydroxyl groups on the HA chains to
form a
gel.
We have conducted a number of preclinical
studies to characterize the safety of this
material.
These studies were consistent with the ISO 10993
standards as well as the FDA guidance document
for an
implant that will reside for greater than 30
days.
We conducted 20 GLP and 7 non‑GLP
preclinical studies, which included cytotoxicity,
irritation, intercutaneous as well as
subcutaneous,
acute systemic toxicity, subchronic as well as
chronic
toxicity going out to one year, a number of
genotoxicity studies, sensitization and
immunogenicity
implantation in the rabbit muscle implant test,
pyrogenicity, hemocompatibility, reproduction, as
well
as clearance.
We found in these studies that Hylan B was
safe and nontoxic at amounts that were equivalent
to
or in great excess to that which was studied in
the
human clinical trial that you will be hearing
about.
So, in summary, we had developed an
HA‑based formulation that we feel is
consistent with
our design inputs for a temporary dermal
filler. Our
preclinical studies show that Hylan B did not
elicit
a significant biological response, indicating
that it
made sense to go ahead and evaluate this material
in
human clinical trials.
I would now like to ask Dr. Dick Polisson
to describe the design of our trial.
DR. POLISSON: Thank you, Jim.
CLINICAL STUDY DESIGN
DR. POLISSON: Ladies and
gentlemen, my
name is Richard Polisson. I am senior vice president
of clinical research at Genzyme Corporation. My
charge in the next 14 minutes or so is to go over
three major areas: first, to provide a very brief
background regarding the biology of aging skin
and how
dermal fillers are used in this condition;
second, to
refresh for you a prior clinical experience with
Hylaform, which exists from two open label,
single arm
studies, one in the U.S., one in Sweden; and,
finally,
to spend most of my time going over three
distinct
clinical research activities involving the clinical
endpoint development, which I will discuss in the
context of what we were calling our control
material
characterization study.
I will try to explain to you our
non‑inferiority approach in the context of
describing
our pivotal trial design and then finally end up
describing our repeat treatment study, which was
designed primarily to look at the safety of
Hylaform
after repeat treatment.
Okay. So this is the condition
under
study, if you will. It's not really a disease per se.
It's really a process of life. Most of us already
have some of this and if not now, then very near
in
the future.
If you can't tell, this is old skin.
I
will just point out to you the fact that there
are
amorphous collections of eosinophilic material in
the
dermis that has been termed by
dermatopathologists
"elastosis." I would like to focus our discussion
here on the dermis because I think that is very
important for this particular discussion.
So the dermis has cells, of course.
But,
in addition, it has extracellular matrix
molecules.
Three I think deserve mention. One is collagen, which
by virtue of its triple helical structure
provides a
structural scaffold to the dermis.
Elastin by virtue of its elasticity
provides resiliency to the dermis such that the
skin
would snap back into place after being retracted.
And, finally, glycocyaminic glycans,
particularly hyaluronic acid, which has a unique
physicochemical state and relationship with
water,
provides an osmotic force that gives the dermis
its
turgidity.
The bad news is that with aging, all of
these molecules become deficient to one degree or
another.
So that's the biology. The
clinical
problem is this, and that is wrinkles. There are many
different types of wrinkles. I have been learning
about all of these types of wrinkles. We have
marionette lines. We have the forehead wrinkles,
glabellar lines.
And the nasolabial fold is the one
that we have chosen to focus on for the purposes
of
our clinical trial.
We have done this primarily because we
feel it's the most challenging in terms of
filler. It
exists in a very high‑motion area and
because of its
sheer length and depth requires a significant
volume
of dermal filler in order to correct.
I think the idea is really quite simple in
that in the dermis, which has deficient
extracellular
matrix, we are really injecting into that space a
material that primarily is manufactured
extracellular
matrix molecules in the form of collagen or
hyaluronic
acid in an attempt to fill out the wrinkle from
below
to give you a more pleasing visual contour.
And then this in the bottom is sort of an
idealized great treatment response, patient
before and
after.
For me as a clinical trialist, however, these
two panels are very important. The question is, how
do we quantify the degree of correction? I will get
into that when I describe our clinical endpoint.
Now to go over some of the prior studies
that we have.
Again, these are single arm, open label
trials.
One of them was performed in Sweden.
It
involved 63 patients from 8 centers, followed for
up
to 24 weeks.
Multiple defects, not just the
nasolabial fold but other defects in the face,
were
corrected, but only one touch‑up was
allowed, which
doesn't really reflect practice at this point in
time.
The endpoint was assessed by the
investigator, a 100‑millimeter visual
analog scale,
and expressed as percent improvement from
baseline.
The top‑level results are that 49 percent
of the defects had a greater than 50 percent
improvement at 12 weeks, 39 percent of the
defects had
greater than a 50 percent improvement out to 24
weeks,
and there were no concerning safety trends in
this
study.
The U.S. study was a bit different in a
number of areas.
It was larger, certainly, involving
216 patients, 6 centers. These individuals were
followed up for up to 12 months, primarily for
safety.
Multiple defects were treated, again
similar to the Swedish study. But in this particular
case, greater than one touch‑up was
allowed, which
reflects more of the standard practice that we
see
nowadays.
Again, the endpoint was assessed in
similar fashion.
Top‑line results, greater than 60
percent of the defects that were treated in this
study
had greater than or equal to a 33 percent
improvement
out to 18 weeks.
And, again, as with the Swedish
study, there were no concerning safety trends.
This is the list of the different types of
defects that were treated in those two
studies. I
believe, as you can see, there were many
different
types of wrinkles, many locations, including the
nasolabial fold but also including the lips, the
forehead.
And, in particular, scars are treated.
These are for the most part acneiform or post‑viral
scars.
Our clinical strategy really drives our
clinical trial design. This is very important.
We
wanted to develop a non‑bovine, non‑collagen
source
dermal filler that was clear, not opaque, and it
did
not require a pre‑implantation skin
test. We wanted
this dermal filler to be comparable to, not
superior
to, but comparable to, the current standard of
care,
which is Zyplast.
We recognized that in order to do that, in
order to get this approved, that we have to
perform a
well‑designed, well‑controlled
clinical trial that
meets regulatory standards.
Let me now talk a little bit about our
clinical endpoint development. Lemperle published his
scale in 2001.
That group designed the scale
specifically to look at efficacy of dermal
fillers.
They evaluated this in three domains: the visual
assessment, live assessment; a photographic
assessment; and a profilometric assessment, in
which
one takes a negative silicon impression of the
wrinkle
and actually gets a depth. That then provides the
gold standard to which the other two domains are
compared and validated.
Now, this is a great scale, six‑point
scale.
One I think would agree that that going from
here to there goes from almost no nasolabial fold
wrinkle to a very severe one. The problem is that
there are other visual signals in this scale that
are
distracting to the individual who might be
scaling
these wrinkles.
Those include different lighting;
different pigments; and, indeed, different
wrinkles on
other parts of the face.
So for our particular trial, we were very
keyed on the nasolabial fold, as I mentioned
before.
So what we decided to do was to take photographic
images of nasolabial folds of varying degrees of
severity and digitize them and morph them onto a
standardized face. Again, the whole idea here is to
focus the individual who is scoring this on the
scale.
Now, this is an animation showing how this
was done.
We are aging this person's face 40 years in
5 seconds.
And so what we see here is a very, very
severe nasolabial fold at the end with redundant
tissue.
Although you may not remember the first one,
it was a perfectly normal face with no nasolabial
fold.
Now, the second part of this whole process
that we think is incredibly important is that we
establish an independent panel review. We recognize
that when investigators evaluate wrinkles in the
live
situation, that there is a potential for
variability
in measurement and a potential for unblinding
because
oftentimes there is a team of individuals where
one
would be the injector and the other would be the
evaluator.
In order to get over that, we elect to
establish this independent panel review and to
have
the photographs of the patients evaluated outside
of
the site at a central location.
So the IPR consisted of two groups of
three board‑certified dermatologists. They were
trained to the scale. They were tested and retested
to establish high intra and inter‑rater
correlation.
At the time of the patient visit,
standardized photographic stereotactic
methodology and
standardized letting was used to take the
picture.
These pictures were then compared to the
photographs
independently by each IPR member, who reviewed
them in
random order.
We have no idea whether this was the
first or the last treatment. They were blinded to
subject, treatment, to site, and to time.
This was the data collection form that
they used, sort of annotating the previous
comments
about the systematic nature of how one collects
the
data in this particular situation. This data
collection form then goes on to data management
and
then is analyzed.
Okay. Now, what do we do with that?
Well, we wanted to evaluate this in our control
material characterization study. We wanted to get
experience with this scale and experience with
the
process of the IPR review.
We also needed to evaluate intra and
inter‑rater correlations using the Genzyme
scale.
Remember, this is almost exactly like the
Lemperle
scale, even to the degree that the written
descriptors
of the wrinkles were the same; and, finally, to
confirm the patient to patient variation so we
could
convince ourselves that the sample size that we
calculated for the pivotal trial was accurate.
This was an open label trial involving
Zyplast only, 32 patients. They had to have a grade
three or four on our six‑point scale
nasolabial fold.
They were touched up at two weeks if less than a
one‑point improvement. And then a final assessment
was made at 12 weeks.
What we found was that this new way of
evaluating wrinkles, this photographic review
process,
was logistically feasible, that the standard
deviation
of 1.28 confirmed the appropriateness of the
sample
size of 108 in each treatment group, and that the
IPR
group showed good inter and intra‑rater
correlations.
So now on to our pivotal trial.
What did
that look like?
The primary objective, very simply,
was to evaluate the safety and efficacy, but the
key
thing here is we wanted to do so in a non‑inferiority
type of approach. And we're comparing ourselves to
the 20‑year gold standard of Zyplast; and,
secondarily, wanted to measure other clinical
effectiveness measures, including the
investigator
live assessment at the site face to face with the
patient as well as patient and physician global
assessments.
A couple of comments about the two fillers
under study.
Many of you may know this, but I'll just
review it for you. Zyplast is cross‑linked bovine
collagen and has 0.3 percent lidocaine in it.
Hylaform is cross‑linked avian hyaluronic
acid. It
does not contain lidocaine. Zyplast is opaque.
Hylaform is clear. Zyplast has a higher concentration
of 35 milligrams per ml; whereas, Hylaform is 5.5
milligrams per ml. Skin testing is required for
Zyplast, and skin testing is not for Hylaform.
Our methodology is as follows.
It was a
double‑blinded, randomized multi‑center
study against
an active comparator. And patients were followed up
and observed for 12 weeks. Both nasolabial folds were
corrected with the same material with one touch‑up
allowed at two weeks but only if less than one‑point
improvement was noted by the investigator at the
site.
The key point here, patients were
blindfolded at the site, blindfolded before the
injector and the investigator entered the room
and
before any material was visible to the
patient. They
remained blinded to the treatment arm throughout
the
study.
Finally, patients in order to really
evaluate whether or not blinding was appropriate
and
good were queried about treatment allocation at
the
conclusion of the study. Dr. Holmdahl will review
that data for you.
Major inclusion/exclusion criteria:
healthy men and women between 30 and 55 years of
age,
‑‑ ethnicity was not an exclusion in
this trial ‑‑ a
negative double skin test to collagen before
randomization, two visible nasolabial folds with
a
live score of three or four, no exposure to
potentially confounding cosmetic therapy or
procedures
for six months, ‑‑ the reason for
this was to evaluate
confounding measurement of the endpoint ‑‑
and no
history of scar‑related diseases, delayed
wound
healing, or keloid formation.
This is a schematic of the trial.
Again,
patients were skin tested here about six weeks
before
randomization.
Two weeks later if they were clean,
they were randomized to Hylaform or Zyplast,
followed
at three days for safety and efficacy.
A key point here is that two weeks after
the first implantation, they were touched up if
the
degree of improvement was less than one in the
investigator's eye. And then again, they were
followed up for three days, two weeks. If they were
not touched up, they went on to 4, 8, and 12
weeks for
both safety and efficacy.
I will parenthetically state that the
proportion of patients touched up was actually
quite
small in this study. It is a very important point.
Now I will try to explain non‑inferiority.
Clinically interpreted, it really implies that if
one
is non‑inferior, the test device in this
case is
comparable to the control. If you remember, that is
compatible with our development strategy in which
we
wanted to develop a dermal filler that was
comparable
to the effect that has been seen in Zyplast but
had
different other characteristics that we think
were
important.
Now, when one does non‑inferiority, one
has to define a margin or window of difference
between
the treatment and control arm that is small
enough or
smaller than a clinically meaningful treatment
benefit.
Remember that we used a six‑point scale
here. A
one‑point difference was considered
clinically meaningful. A one‑point difference was
used as the decision note to touch up or not
touch in
the pivotal study. And so 50 percent of that, or .5,
was considered to be the window that was most
appropriate.
Now, by convention, when one does a
non‑inferiority study, ‑‑ the
reason I am going into
this in great detail is that most of us have done
trials where we are looking at superiority or
drug A
is greater or better than drug B. But in a
non‑inferiority type of approach, one
really does it
by virtue of confidence intervals, which are
constructed around the difference between the
treatment and the control mean.
In this case, if the 97.5 percent lower
confidence interval falls within the margin that
I
have just described, the .5, then one is
considered
non‑inferior.
I think Dr. Holmdahl will show you that in
our trial, we actually met this particular
endpoint.
On the other hand, if one falls outside of that
range,
if the treatment differences are significantly
different, then one is not considered non‑inferior.
Finally, the repeat treatment phase, very
simply, to evaluate safety of repeat treatment
with
Hylan B products and to measure rates of adverse
events associated with re‑treatment and,
very
importantly, to measure Hylan B anti‑IgG
antibodies
and, even more importantly, to determine whether
or
not there is an association of those particularly
laboratory tests with adverse events.
The schematic at that trial, again,
remember, Hylaform‑treated patients
only. So they
have already been in the trial 12 weeks. If they
agreed to go into this study, they were re‑randomized
to receive Hylaform or Hylaform Plus in either
the
right or the left nasolabial fold. They were followed
three days, two weeks, and four weeks for safety.
So I conclude. It is our opinion
that
this study design just described meets the
principles
of a well‑controlled clinical investigation
as
outlined in 21 CFR 860 in that we identified and
recruited and randomized appropriate subjects, who
will receive this product in practice if it is
approved.
We used an active control, which is the
gold standard.
And we did so in a double‑blinded,
randomized fashion.
Our photographic endpoint provides a
systematic method of observation that we feel
minimizes bias and maximizes the blind at the
site.
And a non‑inferiority statistical approach
matches our
clinical development strategy.
Thank you for your attention. I
am now
going to turn the podium over to Dr. Lena
Holmdahl,
who will discuss for you the results of safety
and
efficacy.
Thank you.
CLINICAL STUDY RESULTS
DR. HOLMDAHL: Good
afternoon. My name is
Lena Holmdahl.
I am a senior director in clinical
research at Genzyme. I am also professor of surgery
with about 20 years of clinical experience. I will
present the results to you from the trial that
has
been introduced to you by Dr. Polisson.
This is an overview of what I will
present:
first, that the two populations were
comparable at baseline; that the use of Hylaform
produces a cosmetic correction that is comparable
to
the active comparator, Zyplast; and that the
primary
efficacy endpoint was thereby met; that Hylaform
does
so with the use of less material, leading to less
exposure of patients to implanted material; that
treatment and repeat treatment are safe, at least
after four weeks after treatment; that the
overall
patients; tolerability to Hylaform is excellent;
and
that this leads to an overall favorable risk‑benefit
ratio with Hylaform over standard of care.
This slide summarizes important
information about this study population. Three
hundred, thirty‑nine patients were
consented, of which
23 percent were screen failures, most of which
because
they didn't meet the wrinkle criteria.
Eleven tested positive for bovine collagen
skin tests.
So they were not randomized.
Please keep
this in mind when you compare the safety results
that
patients with positive skin tests to bovine
collagen
were already sorted out and did not participate
in the
study.
In total, 261 patients were randomized,
133 to the Hylaform arm and 128 to the Zyplast
arm.
And, as you can see in the table, there were
three
discontinuations in both groups. In the Hylaform
treatment group, one subject requested to
withdraw and
two were lost to follow‑up. And then in the Zyplast
group, there were two discontinuations due to
adverse
events that were unrelated to the use of the
product
and one patient that requested to withdraw.
This slide summarizes important baseline
characteristics that potentially could affect
outcome
for the two populations that are compared. All of
these factors were the same in the two groups,
which
shows that randomization worked and that the two
groups were comparable at baseline.
Ethnic background was not an exclusion
criteria in the study. This graph shows the ethnic
background of subjects seeking cosmetic
improvement,
as published on the internet by the American Society
of Plastic Surgeons and American Society of
Aesthetic
Plastic Surgery pertaining to 2002. The ethnic
distribution of patients in the trial is shown in
yellow.
The population in the trial is similar to
what has been published. We, therefore, believe that
the trial population accurately reflects the
target
population.
I want to draw your attention to that 80
percent of the patients were Caucasian. So that means
that 20 percent were subjects with skin of color.
Wrinkles were scored at baseline using the
scoring scale that has been described to you by
Dr.
Polisson.
This graph illustrates that the two groups
were comparable at baseline. It also shows that the
investigators scored at baseline the wrinkles
within
the range specified in the protocol for inclusion
into
the study.
As degree of cosmetic correction is by
virtue of its nature challenging to quantify and
at
the same time is one of the very few endpoints of
a
trial that easily lends itself to illustration, I
thought it could be helpful to show some pictures
of
patients in the study before and after
treatment. As
a side note, the patients have consented to
having
their pictures used.
On the left‑hand side is shown Hylaform
patients before treatment and at two weeks after
the
last treatment.
This area here is a nasolabial fold.
Here you can see the results after treatment.
On the right‑hand side is shown a Zyplast
patient at the same time points. As you can see,
there was an improvement in both cases. In fact,
two‑thirds of the patients in both
treatment groups
assessed themselves as better at the conclusion
of the
study.
The FDA has specifically asked us to
present examples of various cosmetic
outcomes. Here
is shown a good outcome of treatment. In the middle,
we see an average outcome of treatment. And to the
right we can see is an example of a poor outcome
of
the treatment.
The primary efficacy endpoint was met.
This diagram again illustrates the results of the
primary efficacy endpoint, showing that the lower
bound of the one‑sided confidence interval
was within
the specified non‑inferiority margin. The reason that
I am showing this diagram is to avoid confusion
about
the difference, or the delta.
The results from the model were based on
the adjusted score, taking into consideration
baseline
factors, including treatment group, study center,
baseline median IPR score, and nasolabial
fold. That
difference, or delta, was ‑.2. What I will show in
the following graphs is the raw score.
This difference, or delta, is ‑.1. This
graph illustrates the primary efficacy endpoint,
IPR
score, at 12 weeks after the last treatment. The bars
illustrate the mean values of wrinkles of the
error
bars, one standard deviation.
The majority of wrinkles did not have any
touch‑ups.
As shown in the graph to the left, the IPR
score was the same in the two groups. This group
consisted of 111 of the 133 Hylaform‑treated
patients
and 119 of the 128 Zyplast‑treated
patients.
The middle bar shows the IPR scores in the
subset of wrinkles that had a touch‑up. That was 22
patients, or 42 wrinkles, in the Hylaform group
and 9
patients, or 14 wrinkles, in the Zyplast group.
The bars to the right show combined
results.
As illustrated in the graph, the numerical
difference that exists at 12 weeks is being
driven by
the subset of wrinkles that had an initial
correction
that was less than one score and, thus, qualified
for
a touch‑up.
The difference, or delta, between the two
groups is ‑.1. That difference is located in the
range between IPR scores two and three.
The cosmetic appearance of wrinkles grades
two and three is shown in this picture. The numerical
difference at 12 weeks, thus, translates into a
tenth
of the difference between these 2 wrinkles,
something
that is not discernible by the eye.
To be clinically meaningful, any
difference needed to be at least one point, 50
percent
of which was used as the non‑inferiority
limit.
According to these predefined criteria, Hylaform
is
statistically and clinically comparable to
Zyplast.
As dermal fillers operate through a
mechanism that is depending on occupational space
to
be efficacious, the volume administered needs to
be
taken into consideration.
The purpose of this slide is to illustrate
and emphasize that Hylaform exhibited a
comparable
efficacy to Zyplast with a smaller volume of
material
used.
This graph is showing the volume
administered to achieve the results. From this
comparison, it is evident that Hylaform can
achieve a
similar result as the comparator with less
volume.
This is particularly apparent in the majority of
wrinkles, that they are not qualified for a touch‑up.
In this subset, the volume of Zyplast needed to
achieve the same correction was 1.4 times
greater.
This graph illustrates the live assessment
of wrinkles at 12 weeks after the last treatment.
That was the secondary endpoint in the
study. This
assessment was done by the investigator in a
face‑to‑face meeting enabling a three‑dimensional
perception of the contour defect, as opposed to
the
IPR scores that were assessed from standardized
photographs.
The bars illustrate the mean values and
the error bars one standard deviation.
Again, the difference, or delta, between
the two groups is ‑.1. And that difference is located
in the range between live scores two and
three. The
same grading template was used for the live
scores as
for the IPR scores. And the cosmetic appearance or
wrinkles live scores two and three is shown in
this
picture.
The numerical difference at 12 weeks,
thus, translates into a tenth of the difference
between these 2 wrinkles, a difference that is
not
visible.
The patients were blinded to their
treatment assignment, as described here earlier
by Dr.
Polisson.
They were, actually, as a part of the study
asked if they knew their treatment assignment.
As shown in this graph, some of them
thought that they knew the treatment
assignment. Some
were right; some were wrong. But, most importantly,
the majority did not know. A proper blinding of the
patients makes patient assessment of outcome
valid.
Given the IPR scores I just presented to
you, one might ask if either of the two dermal
fillers
had any effect at the conclusion of the study
with a
strict treatment regimen that was employed. The
answer to that question is yes, they both had an
effect.
To a certain degree, cosmetic outcome is
in the eye of the beholder. And, therefore, patient
assessment of patient satisfaction must be
considered
as this drives the need for additional
treatments.
Global assessment is the qualitative
composite outcome measure consisting of positive
and
negative effects produced by the use of the
product.
This was a secondary endpoint in the study. Global
assessment was done by both the investigators and
the
patients.
The bars illustrate the mean values of
patients' assessment at 12 weeks and the error
bars
one standard deviation. At the last visit, the
difference in patients' global assessment was ‑.1
on
a 5‑point scale. Both the treatment and the control
group were on average about one, which means that
they
assessed the outcome as better than before
treatment.
None of the Hylaform patients considered
themselves
worse or much worse.
This is important in patient satisfaction
or dissatisfaction with cosmetic correction, governs
the timing of repeat treatment. This is what for a
cosmetic product one might call a clinical
benefit.
This notion of improvement from baseline
was confirmed by the investigators. The investigators
were also asked to qualitatively assess
outcome. The
bars illustrate the mean values of investigators'
global assessment at 12 weeks and the error bars
one
standard deviation.
The difference was, again, ‑.1 on a
5‑point scale. Both the treatment and the control
group were on average about one, which means that
the
investigator assessed the outcome as better than
before treatment.
The next section of the presentation will
summarize results pertaining to the safety of the
product.
Based on the mechanism of action of
Hylaform, our expectation was that the patients
would
come back for repeat treatment and would,
therefore,
have an interim safety assessment in the repeat
treatment phase.
At one percent, adverse events were
captured both during the initial phase and after
four
weeks of the repeat treatment phase. That was a time
point that was considered by us and by the FDA to
be
sufficient to evaluate safety of repeat
treatment.
And the data that we have from the initial phase
support that.
Lastly, immunogenicity results will be
presented.
This diagram shows the definition of
adverse events as stated in the protocol.
Treatment‑emergent adverse events could be
either
procedure‑related or not procedure‑related.
Adverse events with an onset of up to
three days could be deemed by the investigator to
be
procedure‑related. Regardless of onset, adverse
events could be deemed as not procedure‑related. In
this case, the investigator was asked for a
relationship with the device and anesthetic
procedure
or if the adverse event was unrelated to the
treatment.
This slide shows the treatment‑emergent
adverse events during the initial phase. The overall
incidence of adverse events was the same in the
two
groups.
The incidence of procedure‑related adverse
events was also similar. The incidence of
device‑related adverse events was two
percent for
Hylaform‑treated and seven percent for
Zyplast‑treated
patients.
There was one serious adverse event that
was in the Hylaform group. That adverse event was
seen by the investigator to be unrelated to the
product.
There were three patients experiencing
severe adverse events in the Hylaform group and
seven
in the Zyplast group. Finally, there was no
discontinuation because of adverse events in the
Hylaform group, but two patients chose to
discontinue
because of adverse events in the Zyplast group.
There is no news here. This
table shows
the procedure‑related adverse events. They are in
agreement with what has been reported with the
use of
dermal fillers.
That's what one would expect.
The overall incidence between the two
treatment groups was similar. The most common adverse
events were erythema, bruising, swelling, pain,
and
pruritus.
As a side note, the adverse event profile
was the same in subjects with skin of color. And we
have no occurrence of scarring or keloid
formation or
pigmentation disorders in patients with skin of
color
in the Hylaform group.
These are the device‑related adverse
events in the two treatment groups. Two Hylaform
patients experienced device‑related adverse
events.
They were erythema, induration, and
pruritus. Nine
Zyplast patients experienced deice‑related
adverse
events listed here: erythema, bruising, pain, nodule,
necrosis, and stomatitis.
Duration of adverse events is another
factor that needs to be considered in the
evaluation
of the overall safety profile. Using a conservative
approach, the adverse events that could be
attributable to the treatment are the procedure
and
the device‑related adverse events. Most of them had
a short duration and had resolved within a week
in
both treatment groups, as shown in this
table. None
of the adverse events in the Hylaform group had
an
onset after one month. This is, of course, evaluating
safety after two weeks after repeat treatment was
reasonable.
Blood sampling for antibodies to Hylan B
was done in all randomized patients prior to
treatment, 2 weeks after last treatment, and at
12
weeks and measured with an ELISA test. Most
importantly, we looked specifically if titer
levels
were associated with adverse events. And they were
not.
One of the 261 patients tested developed
a significant increase in Hylan B IgG. That patient
had been treated with a single injection of
Hylaform.
The increase in titer was detected at the four‑week
visit.
Keep this in mind when assessing repeat
treatment results.
The adverse events that that specific
patient had were injection site bruising and
headache,
none of them consistent with an immune‑mediated
response.
In this context, it might be appropriate
to mention that the incidence of bovine collagen
skin
tests was 3.2 percent of the screened population
and
that screening for potential hyperreactivity to
Hylaform was not done.
Finally, a brief summary of the interim
safety data from the repeat treatment phase. These
results pertain to data collected up to four
weeks
after the repeat treatment. Ninety‑six of the 133
patients who were treated with Hylaform opted to
enter
into the repeat treatment phase. Overall, the types
of adverse events that did develop were the same
as in
the initial phase.
One patient developed an abscess at the
treatment site that needed intervention and,
thus, was
classified as serious. It did resolve without
sequelae and was of moderate intensity. There were no
severe adverse events in the repeat treatment
phase
and there were no discontinuations because of
adverse
events.
The patients who enrolled in the repeat
treatment phase were again tested for Hylan B
antibodies in blood samples. All of these patients
had previously been exposed to Hylaform, some of
them
twice.
None of the 92 or the 96 patients from which
antibody results are available developed a
significant
increase in Hylan B IgG during the first four
weeks of
repeat treatment.
So, to conclude, we believe that these
results demonstrate that Hylaform exhibits the
same
degree of cosmetic correction, that Hylaform is
well‑tolerated without the skin test, that
Hylaform
has a similar safety profile after repeat
treatment.
And we believe that this translates into a
favorable
overall risk‑benefit ratio.
Thank you.
CONCLUSION
MS. STEWART: I would just like
to present
some of the key points that we have provided
today:
the fact that Hylaform has been available
worldwide
and in Europe beginning in 1996, we have shown in
extensive preclinical testing that Hylaform is
safe,
we have demonstrated in a robust clinical trial
that
it is comparable to Zyplast in both safety and
efficacy, and we truly believe it is safe to use
in
repeat use and that our results support its use
in
correction of soft tissue contour deficiencies.
Thank you. Now we are available
to answer
any questions the panel may have.
ACTING CHAIRPERSON CHANG:
Questions from
the panel?
Dr. Blumenstein, do you have any specific
questions regarding the study design?
MEMBER BLUMENSTEIN: I might have
missed
it, but did you show just changed scores, just
changed
scores?
DR. HOLMDAHL: No. What I showed was the
scores at 12 weeks. I didn't show any changes in
scores.
MEMBER BLUMENSTEIN: What I'm
trying to do
is get the magnitude of change that happened in
the
Zyplast group, for example.
DR. LARHOLT: I'm Kay Larholt
from Genzyme
Corporation, the biostatistics group.
We had established that the efficacy
parameter that we were measuring was the week 12
score.
and, therefore, that's what we looked at. We
did not look at changes from baseline.
MEMBER BLUMENSTEIN: Do you have
baseline
scores?
DR. LARHOLT: We have baseline
scores that
we have shown.
Those are the IPR median scores that
were at baseline, the live score as well.
Lena had showed the IPR scores at
baseline.
She had shown that they were 3.5 in the
Hylaform group and 3.6. The mean was 3.5 in the
Hylaform group and 3.6 in the Zyplast group,
which
shows the means at baseline for using the live
score.
This was what was used for enrollment into the
study.
MEMBER BLUMENSTEIN: I may have
questions
later.
ACTING CHAIRPERSON CHANG: Dr.
Newburger?
MEMBER NEWBURGER: I have a
question. In
the population of people who were treated a
second
time, where you say that the incidence of adverse
events is similar between the two groups, in the
people who were treated de novo in your study the
first time, very few people are reported to have
nodules.
I think it was at a zero or one.
In the repeat study, individuals who had
Hylaform the second time, I count 12 people who
had a
3 or more days induration. Now, I understand there's
a difference in that there is a diary the second
time
around and there wasn't. However, since the protocol,
I think, didn't it show investigator observation
the
first time at three days? Why is there such a
disparity?
Because 12 out of 96 is a tremendous
proportion.
DR. HOLMDAHL: I would like to
call on Dr.
Kingma to answer that question.
DR. KINGMA: Hi. My name is
Wytske Kingma.
I am heading up the safety department at Genzyme.
With regard to the nodules we find in the
study, it's important to note that in the initial
phase, the nodules as such were assessed by the
physician.
We did not have any in the Hylaform group,
and we have three in the Zyplast group.
In the repeat treatment phase, as you
pointed out, the patients used a diary. It was
actually anything that were lumps or bumps that
were
coded. In
order to collect adverse events, you need
to code them in the dictionary. So they code to
nodules.
As we are, of course, concerned about
whether or not that nodule is a true nodule in
the
immunological sense, we actually looked at
those. The
majority of the mean onset for all those 22
patients
who had reported lumps and bumps was 1.2 days,
with
the majority of them starting right at the time
of
injection and actually some commenting that they
felt
that the material under their skin and noting
that as
a lump or bump.
In addition, the mean duration of the
entire group was only 12 days. There were no nodules
that actually had the delayed onset, which is
what you
would otherwise expect with regards to a possible
immunological reaction.
Does that answer your question?
MEMBER NEWBURGER: Yes, sort of.
ACTING CHAIRPERSON CHANG: Dr.
Halsey?
MEMBER HALSEY: I have a question
about
the exclusion criteria. Reading the documents, it
seemed that patients were excluded from the study
if
they had allergies to avian proteins as well as
bovine
proteins.
Is that correct?
How was that determined? Was
that
patients' reported history of allergy or was
there
some test, either a skin test or a blood test of
atopic status?
DR. POLISSON: Those exclusions
were by
history.
MEMBER HALSEY: Reported history
from the
patient, not a physician's evaluation?
DR. POLISSON: I would like
actually to
get some clarification from that. May I ask Laura
Fleming to come forward and specifically address
that?
MS. FLEMING: Hi. I'm Laura Fleming from
Genzyme clinical research.
The history is avian source protein
histories.
The patients were asked if they were
allergic to eggs. It was patient‑reported.
Patients
were only excluded for bovine if they had
positive
skin tests.
MEMBER HALSEY: You did not
exclude
patients with other allergies, seasonal
allergies,
perennial rhinitis, or anything like that?
MS. FLEMING: No, we did not.
MEMBER HALSEY: Not even if it
was severe?
MS. FLEMING: That's correct.
MEMBER HALSEY: I would also like to ask
a little bit of detail about the IgG ELISA that
you
used. How
was that standardized and quantified?
Are
these titer units, this 50, or is that nanograms
per
ml of IgG or what?
MS. RICHARDS: I'm Sue Richards,
Genzyme
immunology department.
The immunologic assay that was used was an
indirect ELISA.
So basically Hylaform was coded into
the microtiter plate well. It was then blocked using
nonfat dry milk.
Patient sera was then added using a
twofold serial dilution series. And then any bound
antibody was detected using an HRP anti‑human
IgG
conjugate.
Certain colorometric reaction was then
determined.
Now, the titer was assessed using the
negative control, which was a normal human serum
sample that was tetanus‑positive because we
also used
tetanus as a positive control for coding in the
assay.
In that particular sample from the
validation, it was determined that an ODE value
greater than .5 was what was considered as
negative
reactivity of normal human serum because we did
discover that we had a human serum effect in the
assay.
So the titer values are the reciprocal of
the highest dilution that gave that particular
cut
point value.
MEMBER HALSEY: Then you used a
fourfold
rule. So
it would have to be four times the titer of
that to have been concluded what you concluded?
MS. RICHARDS: No. Since we do have
background reactivity of normal human serum in
this
particular assay, the fourfold rule was based on
each
patient's own baseline. So we had a true baseline
value of that particular individual. So a sera sample
was drawn before treatment and then a titer
determined
on that if there was background reactivity. And then
a fourfold or greater increase above that
patient's
own baseline was what was determined as showing
positivity in the assay.
MEMBER HALSEY: Just to address
one
further technical detail, the IgG ELISA, did you
show
inhibition with soluble forms of hyaluronic acid
to
show that what we're really measuring is antibody
to
HA, rather than something else?
MS. RICHARDS: What we had looked
at
subsequently, we did not do inhibition
analysis. What
we had looked upon subsequently in the positive
patient was we had looked at alternative avian
sources
and alternative bacterial sources of HA and had
ascertained that the reactivity was specific to
Hylaform B, the cross‑linked avian
material.
MEMBER HALSEY: So these patients
didn't
have antibody that you could measure to other
avian
proteins?
MS. RICHARDS: Correct.
MEMBER HALSEY: Did you measure
IgE to any
of these?
MS. RICHARDS: The initial conjugate that
was used in the screening assay, although the
vendor
did specify it was anti‑IgG, we did do
cross‑reactivity analysis and ascertained
that it is
cross‑reactive to IgM and also IgE.
So the positivity at the beginning would
show cross‑reactivity to IgE if it was
present. So if
we did see an increase, we would have seen it
also for
IgE.
ACTING CHAIRPERSON CHANG: Dr.
Bartoo?
MEMBER BARTOO: You've presented
data
outside the U.S. in 30‑plus countries with
over
500,000 units distributed. My first question is, what
is the ethnic diversity within those treatments
outside the U.S. that you have presented here?
The second question I have is that I
understand that in the U.S. pivotal study, your
representation of ethnic groups is in proportion
to
what typically is treated. However, you still have
very small numbers of certain groups, especially
African Americans. There's only three subjects in
that group.
So I would like to hear your justification
for why you feel that is enough in terms of
safety
data in this group.
DR. POLISSON: With respect to
the two
clinical trials that I reviewed and presented to
you,
most of those patients were Caucasian, but I can
actually get those numbers for you and present to
you
later in the panel. I don't have them on the tip of
my tongue.
Now, with respect to other worldwide use,
I, quite frankly, don't think we actually track
that
data.
But, again, if that's a mistaken or misspoken
comment, then we'll correct that later.
ACTING CHAIRPERSON CHANG: And
the second
question was, do you as a sponsor have a feel
that the
study is adequate, even though there are three
patients who are of African American descent?
DR. HOLMDAHL: I would like to
call on one
of our investigators, Dr. Monheit, who has
experience
with patients with skin of color from his
practice.
DR. MONHEIT: Hi. I'm Dr. Gary Monheit.
I'm a dermatologist from Birmingham, Alabama
associated with the Department of Dermatology in
the
University of Alabama Medical Center.
I have a 20‑plus‑year history of using
injectables in a diverse population in Birmingham
and
through a portion of Alabama. First, I'll address the
fact that in our study group, we have the three
African American patients, whom I took care of
and
treated.
Their efficacy was the same and as good as
all of the other patients treated, and there were
no
adverse events in those three particular
patients.
In addition to that, I've got many years
of experience injecting patients of color,
including
African Americans, with Zyderm, Zyplast
injectable
fillers.
I have found that there is very little in
the way of adverse events among the populations
I've
treated with Zyplast and Zyderm of African
American
descent as I have found among Caucasians.
The things that we have always worried
about have been keloid scars, the possibilities
of
pigmentary dischromias, hyper and
hypopigmentation.
I found that we get probably the same degree of
pigmentation problems as we get in people who
have
prolonged erythema, who then may get
pigmentation.
That's probably the derivation of it. It's an
inflammatory response that can lead to
post‑inflammatory hyperpigmentation.
When we have seen this with Zyderm and
Zyplast, it is treated in the same way we have
treated
hyperpigmentation of other causes. And that's with
bleaching agents and skin creams and exfoliating
agents.
I have never seen a keloid in my 20 years
of experience treating African American
patients. I
think part of the reason why is we're treating
mainly
the mid‑face area and keloids are very rare
in all
diverse populations of people.
Thank you.
ACTING CHAIRPERSON CHANG: Dr.
Newburger?
MEMBER NEWBURGER: Obviously you
have
given a great deal of thought and care in the
design
of the study and have considered immunologic
compatibility.
I am wondering since in the
literature, the reports of reactions, adverse
reactions, to Hylaform have been what appear to
be of
the delayed hypersensitivity type, have you
looked at
all that t‑cell response to the material?
DR. DeLUSTRO: My name is Dr.
Frank
DeLustro.
I'm with Global Biodevice Development.
I
am here as a consultant for Inamed. I have no
financial involvement with either of those
companies.
I would like to address that question a
little bit.
Perhaps you could put on slide H010.
The
company did look at the data and sorted out
reactions
which could potentially be ascribed or
immunological
in nature.
What we did was to take a look at any
incidences of erythema, redness, induration,
swelling,
pruritus in any combination which occurred in
patients
in the absence of bruising at those sites and
which
occurred at a duration of greater than 14 days.
MEMBER NEWBURGER: Excuse
me. Is it
occurred at greater than 14 days or ‑‑
DR. DeLUSTRO: Excuse me. No, no.
Had a
duration of grater than 14 days. We also did a cut at
greater than seven days with the same results.
What I will show you is a cut at greater
than 14 days since our experiences with other
injectables demonstrates that those reactions
typically last four weeks at a time. And we're real
happy when they go away.
You can see from this table that, in fact,
what we saw in the initial phase of the study was
that
there were only two patients in the Hylaform
group
that fit any of this criteria. They were typical
erythema and in a second patient some pruritus
and
induration, I suppose, to nine subjects that
demonstrated this type of erythema or pruritus in
the
Zyplast group.
These reactions, as you have heard
probably too extensively by now, are not truly
indicative of immunologically mediated events but
are
events of reaction within the dermis to the
material.
You can see that with removal of
hypersensitive patients from the Zyplast group
with
the double skin testing procedure which resulted
in
3.2 percent of the population being eliminated
prior
to treatment ‑‑ and that is
consistent with the
literature of allergic reaction rates to
injectable
collagen.
With that elimination, one still sees
approximately a 7 percent rate of these
nonspecific
indicators, as opposed to the 1.5 percent seen
with
Hylaform.
So it's clearly far less.
That little tiny footnote in the bottom is
also important.
What that states down there is that
in the second group, which received not only the
primary treatment but went on into the repeat
phase
and were retreated, of that 96 patients, none of
these
symptomologies were seen. No conditions that fit this
inflammatory categorization were seen at all.
Could I have the next slide? I
think this
data specifically on the Hylaform study in
conjunction
with what we know about Hylaform from a worldwide
study demonstrates that, in fact, it does not
have
significant incidence of immunologically mediated
hypersensitivity.
As you can see in the first point, the
published studies of hypersensitivity to
hyaluronic
acid dermal fillers is approximately .42 percent,
but,
in fact, if you look specifically at Hylaform
within
those numbers, it actually is about .2
percent. That
is clearly a logarithmic level lower than what is
seen
with the injectable collagens in the dermal
area. In
addition, the adverse event rate seen with
Hylaform on
a worldwide basis is approximately 0.1 percent, a
very, very low level.
So I think in terms of your question, I
think the incidence, potential incidence, of
immunological reactions to Hylaform is
exceedingly
unlikely based on what we have seen.
MEMBER NEWBURGER: I'm
sorry. That wasn't
my question.
My question was, have you looked at
t‑cell recognition?
DR. DeLUSTRO: T‑cell
recognition, as we
know from bovine collagen, would occur with the
same
symptomology.
So if you look at the capture of
clinical symptoms, one sees, in fact, the same
clinical picture of reaction.
When you look at a delayed type
hypersensitivity reaction in a bovine
collagen‑mediated reaction, one sees the
same
symptomologies occurring. And that we have studied
for quite some time.
So by looking at the clinical
symptomology, one captures the potential
reactions
that are going to occur without looking at the
specific etiology, whether it's t‑cell or
antibody‑mediated.
ACTING CHAIRPERSON CHANG: Dr.
Miller?
MEMBER MILLER: In your study,
you
excluded people who skin‑tested positive
against
collagen and also I guess avian proteins. That was
done by skin test or by history only that they
exclude
them?
DR. DeLUSTRO: No. That was by history.
And that history of allergy or sensitivity to
avian
proteins or bovine proteins is consistent with
the
existing package labeling for Zyplastic control
material.
MEMBER MILLER: So what do you
think would
happen if you took a group of patients who were
positive in their reaction to bovine collagen and
you
gave them your product?
DR. DeLUSTRO: I think our
worldwide
experience actually speaks to that. In Europe,
outside the United States, where Hylaform has
been in
use since '96, the first population to be treated
with
Hylaform, in fact, was the built‑up
population of
subjects who had bovine collagen
sensitivity. We know
from the literature and experience with Hylaform
in
Europe that, in fact, those patients were treated
very
successfully with the material.
MEMBER MILLER: Do you still
recommend or
are you recommending for the product that if it
is
approved, that it not be administered to people
who
have a history of reactivity to avian proteins?
DR. DeLUSTRO: We would suggest
that as a
precautionary statement in the package insert.
MEMBER MILLER: Just one other
question.
Is there some avian protein present in the
Hylaform
preparation, some minimal amount?
DR. BURNS: There's about 0.01
percent
avian protein per ml in Hylaform.
MEMBER HALSEY: My understanding
is that
there was .45 percent of the mass in the product.
DR. BURNS: Absolutely not.
MEMBER HALSEY: That's what was
here.
Okay.
DR. BURNS: 0.01 percent protein.
ACTING CHAIRPERSON CHANG: Dr.
Blumenstein?
Dr. Doull next.
MEMBER BLUMENSTEIN: Was Zyplast
effective
in this study?
DR. LARHOLT: We chose Zyplast as
a
comparator because of this data.
ACTING CHAIRPERSON CHANG: Please
speak
into the microphone. Identify yourself.
DR. LARHOLT: I'm Kay Larhout
from
biostatistics from Genzyme.
We chose Zyplast as the comparator because
it is the gold standard. It has been used 20 years.
We show that at the end of the study, as Dr.
Holmdahl
has shown, the life scores were on average one
point
better than they had been at baseline, that the
investigator and patient‑level assessments
were both
positive at 12 weeks. And those were significantly
different from zero. So we thought that yes, Zyplast
was effective in this study.
I will let Dr. Holmdahl talk a little bit
about the differences in this study compared to
how
Zyplast is used in practice.
MEMBER BLUMENSTEIN: All I'm
asking is,
was there a statistical test done to show that
Zyplast
was effective in this study?
DR. LARHOLT: No, there was not.
MEMBER BLUMENSTEIN: Well, then
can I
conclude from that that it wasn't or that you
didn't
do the statistical test? That's what I'm trying to
get to because if you demonstrate non‑inferiority
to
something that is not effective, then you haven't
done
anything.
DR. LARHOLT: We did not test
statistically whether Zyplast was effective. However,
we feel that the result we have shown shows that
Zyplast still was effective at 12 weeks in the
study
and, therefore, shown comparability to it shows
that
we are non‑inferior to an active
comparator.
MEMBER BLUMENSTEIN: I am
convinced that
you have shown non‑inferiority to Zyplast,
but I am
concerned about whether Zyplast was effective.
DR. LARHOLT: I think that maybe
Dr.
Holmdahl can talk about the actual use of Zyplast
in
the study that may be different from how it's
used and
how it's been shown in different studies.
DR. HOLMDAHL: Well, if you
recall the
graphs that I showed, both the live scores show
that
both Zyplast and Hylaform had an average of about
one
point improvement at 12 weeks and also the global
assessment, both investigator and patients'
global
assessment, were about average of whether it
shows or
it translates into that they rated themselves as
better.
So I think from a clinical perspective,
there is no doubt in the study that there was an
effect at 12 weeks. I would also like to call on Dr.
Monheit, who was one of the investigators, to
give his
view of this.
MEMBER BLUMENSTEIN: Well, the
problem is
I don't have the standard deviation. I have no idea
of the variability for the patients in this
study. So
I don't know whether Zyplast was truly effective
in
this study.
ACTING CHAIRPERSON CHANG: Do you
have
data to show about the efficacy, sir, of Zyplast
to
answer that question?
DR. MONHEIT: No. I'm not talking about
data. I'm
talking about clinical experience.
MEMBER BLUMENSTEIN: That doesn't
matter.
ACTING CHAIRPERSON CHANG: Thank
you.
MEMBER BLUMENSTEIN: My next
question is,
in your statement of the primary analysis that
you
were going to do, you said that you were going to
have
a combination of a two‑sided test of
superiority and
a one‑sided test of non‑inferiority
that was used for
the primary efficacy endpoint. The test of
non‑inferiority was considered to be the
primary
analysis.
So you presented that. And I
believe it,
for a change.
(Laughter.)
MEMBER BLUMENSTEIN: And then you said if
the non‑inferiority test was demonstrated,
the test of
superiority was to be performed as a secondary
analysis.
So you demonstrated non‑inferiority.
Where is your test of superiority?
DR. LARHOLT: We did not present
the test
for superiority because it was obvious from the
results that said that the Hylaform because of
the
negative difference, the ‑.2, would not
show
superiority to Zyplast.
MEMBER BLUMENSTEIN: I just
wanted to say
it.
You're not superior, right?
DR. LARHOLT: No, no.
MEMBER BLUMENSTEIN: Okay. Thank you.
DR. LARHOLT: We're not, but that
was not
the primary endpoint. The primary endpoint was
non‑inferiority.
ACTING CHAIRPERSON CHANG: Dr.
Doull has
a question and then Dr. Halsey.
MEMBER DOULL: I may have missed
it in
your material, but can you tell me how much
divinyl
sulphone and formaldehyde are in your product?
DR. BURNS: There's approximately
2.3
parts per million total formaldehyde in the
product.
About one part per million is actually free. And for
divinyl sulphone, it's about two parts per
million
divinyl sulphone free cross‑linker.
There's also a hydrated form of that
product, which is about ten, less than ten parts
per
million.
MEMBER DOULL: That's the amount
in there?
DR. BURNS: Those are actually
our
specifications.
So the amount of material in there is
actually less than that. I think typically we'll be
able to measure about one part per million
divinyl
sulphone.
ACTING CHAIRPERSON CHANG: Dr.
Halsey and
then one other.
MEMBER HALSEY: I wanted to
follow up on
the protein contamination. I am looking at the
documents we were presented. The protein was
determined by Lowry on 42 batches. The protein
content ranged from .12 to .85 percent with an
average
of .83.
Is that wrong? Did I read that
wrong?
That's different than .01 percent.
DR. BURNS: Absolutely. Let me check on
that and get back to you. Obviously you have the data
in front of you, but I will get back and check on
that.
MEMBER HALSEY: Has anybody done
any skin
testing or patch testing with this vinyl
sulphone? Is
this something we should consider, too?
DR. BURNS: We haven't done any
skin
testing with it per se. We have done sensitization
studies with Hylaform and immunogenicity studies,
the
typical sensitization studies, Ames or the Guinea
pig
maximization tests. We have done repeat injections in
a rabbit intramuscular test and then looking for
sensitization following a challenge.
MEMBER HALSEY: Those are all
preclinical.
DR. BURNS: Those are
preclinical, but we
haven't done any work specifically looking at
vinyl
sulphone itself.
MEMBER HALSEY: Has anybody done
skin
tests or patch tests with this product in humans?
DR. KINGMA: Hi. Wytske Kingma, Genzyme.
As part of the skin testing, as you know,
any hyaluronic acid has been widely
available. In
general, there is no skin testing.
In the literature, as you may be aware,
there are some reports where subsequent to a
reaction
patients were skin tested. One of those series is
actually from Dr. Lowe, who presented in 709
patients
that 2 Restylane and one Hylaform patients
actually
were having reactions.
He added another three patients to that
with a total of six. Five of those were skin tested.
One of those was actually negative to everything,
despite the reaction. And the other four were
positive.
That's a mix of Hylaform with Restylane.
In post‑marketing settings, we found both.
We found that patients will actually skin test
negative and had a reaction; the other, reverse,
as
well, that if you had patients positive, for
example,
to other dermal fillers or there was a delayed
sensitivity, that they have been continued to be
receiving it well. So we don't think that the skin
testing itself is a very predictive measure of
seeing
who will have a reaction as a means of detection.
ACTING CHAIRPERSON CHANG: Last
question.
Dr. Diegelmann?
MEMBER DIEGELMANN: Dr. Burns,
you
mentioned that the average molecular weight is
between
four and six million. What percent are the small
molecular weight products in the ‑‑
DR. BURNS: That molecular
weight, by the
way, is the Hylan A. And then that gets cross‑linked.
Once it's cross‑linked, you basically have
an infinite
network.
But we have analyzed for any lower
molecular weight oligomers that may be in the
product.
It looks like about less than probably five
percent of
it by mass would be less than about three or four
hundred thousand in terms of molecular weight.
I don't know how low you want to go.
If
you want to go to about a 20,000, the percentage
goes
down accordingly in terms of the amount of
material
that is there.
So not very much there, maybe some but
not much.
MEMBER DIEGELMANN: Do these low
molecular
weight products increase with aging, with
storage?
DR. BURNS: The proportion that
is free
and not modified does not change in a significant
way,
but you will see a decrease over a period of 2
years
from about 500,000 molecular weight in terms of
the
initial material that might be free to about 300‑350.
MEMBER DIEGELMANN: I am just
concerned
about the small, real small, molecular weight
compounds that can cause angiogenesis and
increased
inflammatory or fibrotic responses.
DR. BURNS: Yes. And it's a good
question.
Whenever I look at that data, I always am
cautioned by the fact that most of that work is
in
vitro.
There's a lot of work that shows that
exogenously added low molecular weight material
in the
setting that we are using it has certainly a
potent
type of biological activity.
We also have a lot of animal data in vivo
biological work with these materials that
indicate
that the site where it's injected appears to be
healing in a fairly normal way.
ACTING CHAIRPERSON CHANG: Unless there
are any very pressing questions from the panel,
we're
going to take a five to seven‑minute break
so that the
FDA may do their presentation. Let's reconvene at ‑‑
MS. STEWART: Dr. Chang?
ACTING CHAIRPERSON CHANG: Yes?
MS. STEWART: May we answer two
questions
that we weren't quick enough on one to Dr.
Blumenstein?
ACTING CHAIRPERSON CHANG:
Yes. On ones
previously asked, yes, please.
MS. STEWART: And one to Dr.
Bartoo.
DR. POLISSON: This is the
question
relating to the ethnicity of the patients who
enrolled
in the two trials. One was done in the United States
and was 216 patients. Only three percent were
patients of color. Ninety‑seven percent were
Caucasian.
In the Swedish study, 95 percent of
patients were Caucasian; 5 percent were patients
of
color.
DR. LARHOLT: I'm Kay Larholt
from the
biostatistics department at Genzyme.
To answer your question, Dr. Blumenstein,
about the standard deviation, we do feel that in
the
clinical study report, table 11.5, the standard
deviation for the Zyplast group at 12 weeks is
1.1.
The standard deviation for the change between the
two
groups is approximately .8. That comes out of the
model.
So they're approximately in that range
between .8 and 1.1 depending on what score you're
looking at.
MEMBER BLUMENSTEIN: The change?
DR. LARHOLT: Not the change, the
difference between the 2 scores at 12 weeks, the
different score.
The standard deviation on that is
about .8.
MEMBER BLUMENSTEIN: .8?
DR. LARHOLT: Yes. The standard error is
.8.
MEMBER BLUMENSTEIN: Standard
error or ‑‑
DR. LARHOLT: Is .08. Therefore, the
standard deviation is approximately .8.
MEMBER BLUMENSTEIN: So you're
saying the
standard deviation at 12 weeks for Zyplast was
1.1.
DR. LARHOLT: Yes.
MEMBER BLUMENSTEIN: And the
standard
deviation for the difference in the mean,
standard
deviation was .8?
DR. LARHOLT: Yes.
MEMBER BLUMENSTEIN: Thank you.
ACTING CHAIRPERSON CHANG: Thank
you very
much. We
are going to take a short break, reconvene
at ten after.
Thank you.
(Whereupon, the foregoing matter went off
the record at 3:06 p.m. and went back on
the record at 3:15 p.m.)
ACTING CHAIRPERSON CHANG: Good
afternoon.
We're reconvening. And we invite the FDA to begin its
review with Dr. Herbert Lerner.
DR. LERNER: Thank you.
FDA PRESENTATION
INTRODUCTION AND CLINICAL REVIEW
DR. LERNER: Good afternoon. Dr. Chang,
Dr. Krause, members of the panel, and guests, I
am Dr.
Herbert Lerner, a reviewer in the Plastic and
Reconstructive Devices Branch of the ODE and team
leader for this PMA. That's PMA number 030032,
Hylaform viscoelastic gel sponsored by Genzyme
Corporation.
I would just like to mention the others on
our team who had input into this
presentation. Dr.
David Krause will follow me immediately and
present
the preclinical data. I will then present the
clinical summary. Ms. Phyllis Silverman will come up
and provide the statistical analysis.
Others on the team included David Kaplan
reviewing some of the preclinical data, Peggy
Mayo
from Office of Compliance, Linda Godfrey from the
Office of Compliance, and Jack McCracken and Mary
Lou
Pijar of the labeling issues on the PMA.
Dr. Krause?
PRECLINICAL REVIEW
EXECUTIVE SECRETARY KRAUSE: Good
afternoon.
I'm donning the other hat now.
Besides
being the executive secretary of the panel, I
occasionally get to review stuff.
I just wanted to say that the company did
extensive preclinical testing, which included
biocompatibility as well as proof of concept and
many
different studies. It would take hours for me to get
up here and try to go through it all.
I am kind of just focusing on the studies
that I think are appropriate to mention. The company
successfully passed irritation testing, which was
performed via intracutaneous and subcutaneous.
Sensitization and immunogenicity were studied via
immunization subchronic toxicity, Guinea pig
dermal
sensitization, delayed contact
sensitization. Again,
these are animal tests.
Cytotoxicity was assessed, acute systemic
toxicity, hemocompatibility, implantation via
muscle
implantation studies in rabbits for 7 and 30
days.
Mutagenicity was assessed using the Ames
mutagenicity test and three mammalian cell tests,
the
induction for HGPRT mutation, chromosome
aberrations,
and also the test for morphological cell
transformation.
Subchronic tox was looked at via
subchronic intraperitoneal toxicity,
immunization, and
subchronic toxicity. Chronic toxicity,
carcinogenicity were assessed via the one‑year
subcutaneous toxicity study. Also, the company looked
for reproductive effects. They studied
pharmacokinetics and pharmacodynamics.
One thing that has come up ‑‑ and a
question was asked about this ‑‑ that
was of interest
to us is that in the manufacture of the product,
there
is a question about formaldehyde and the fact
that as
patients get reinjected, is there going to be a
fairly
large amount of formaldehyde or could that be a
problem?
The information that we received is that
the product contains a specification for 2.3 ppm
but
usually has less, of which about one ppm is what
we
would call free.
So you would expect that if this
material were to come out of the product, it
would do
so at a fairly slow rate.
What we thought was a critical factor was
that if you look at the level of formaldehyde,
which
is a normal body metabolite, you would find that
the
normal serum and tissue levels for formaldehyde
are
between 3 and 12 micrograms per gram, which is
about
the equivalent of 3 to 12 parts per million.
So, in actuality, the product would be
adding a negative amount of formaldehyde. In other
words, formaldehyde from the body would seep into
the
product, rather than the other way around. So
formaldehyde really is not an issue as far as we
have
concluded.
That is really all I have. Thank
you.
DR. LERNER: The object of my
clinical
presentation today is to provide a summary of
Genzyme's Hylaform clinical study and to
highlight the
issues pertaining to the safety and effectiveness
of
the study device.
The sponsor's study purpose is to evaluate
the safety and effectiveness of Hylaform
viscoelastic
gel when used for cosmetic correction of contour
deformities of the dermis of the face.
The study I am about to present corrected
only nasolabial folds. I will be asking you a
question at the end of my presentation regarding
the
study and the indications cited above.
As outlined previously by the sponsor,
this was a prospective, multi‑center,
randomized,
double‑blinded, parallel group study
comparing
Hylaform and Zyplast in the nasolabial fold
during the
initial 12‑week treatment and Hylaform and
Hylaform
Plus during the extended treatment period.
The sponsor has not included any efficacy
data for the extended treatment phase of the
study,
and only four weeks of safety data for possible
immunologic responses were presented in the
PMA. The
sponsor at this time does not seek approval for
Hylaform Plus.
The sponsor has carefully gone over all of
the inclusion and exclusion criteria. And I will
highlight just a few, again, a wrinkle severity
score
of three or four on the six‑point grading
scale, a
negative skin test to collagen implant, and two
fixed
facial sites, fully visible nasolabial folds,
which
were both candidates for correction. Again, patients
could not be pregnant and had to agree to use of
contraception.
Exclusion criteria included a known prior
or present positive skin test to the collagen
test
implant; have received prior therapy, including
dermabrasion or facelift during the previous six
months; and previous tissue augmentation or other
wrinkle/fold therapies within the past six
months.
The treatment protocol, as outlined by the
sponsor, included a screening period, collagen
skin
testing times two per patient, randomization, and
treatment.
Patients could have a touch‑up at two
weeks.
It should be noted that all patients were
skin tested.
Randomization took place after the skin
testing.
And touch‑up was indicated if there was not
a greater than one‑point improvement in the
grading
scale.
Also note that standard photography was taken
at each visit time.
During the initial phase of the study,
both nasolabial folds were treated. As I mentioned,
photographs were taken. An investigator wrinkle
assessment was performed. Touch‑up for the patients
was for 12 weeks starting after the touch‑up
if one
was needed.
In the repeat phase, the treatment was
offered to patients who had only received
Hylaform in
the initial phase. They must have finished the
initial phase.
They were randomized on a side‑to‑side
basis and offered a treatment of Hylaform or
Hylaform
Plus.
Of the 133 patients who finished the
initial phase of the study, 37 did not re‑enroll
in
this phase.
The main reasons for not re‑enrolling
were scheduling conflicts, prior restricted
therapies,
dissatisfaction, or no interest, patients lost to
follow‑up, and two people were trying to
get pregnant.
In the repeat phase, Hylaform and Hylaform
Plus were randomized. There was an investigator
assessment.
Again, photographs were taken at each
visit.
And there was a patient global assessment
at each visit.
Again note that the patients were
studied for 12 weeks, but only 4 weeks of safety
data
was presented for this PMA.
The wrinkle assessment scale, as you have
seen, was a validated six‑point reference
scale with
reference photographs that classified the deep
facial
wrinkles, zero representing no lines or folds and
five
representing severe lines or fold.
The clinical endpoints of the study, the
primary phase was to evaluate the efficacy or
non‑inferiority of Hylaform for the
correction of
nasolabial folds as compared to Zyplast. This was
done using serial photographic documentation and
blinded IPR scores at 12 weeks. The second was to
evaluate the safety of Hylaform as compared to
Zyplast
determined by the rates of adverse events
associated
with the use of each product.
A secondary objective was to evaluate the
clinical utility of Hylaform with respect to
physician
assessment and patient self‑assessment.
For the repeat phase, the endpoint was to
evaluate the safety of repeat treatment with
Hylan B
gel products.
In particular, the sponsor added this
phase to assess the safety of the device after
repeat
maintenance doses by determining the presence or
absence of an immunologic response by measuring
serum
Hylan B, IgG, antibodies and, again, to evaluate
the
efficacy or non‑inferiority of Hylaform
Plus versus
Hylaform for the correction of nasolabial fold
contour
defects.
The same secondary endpoint was for this
part of the study.
As you have already heard, both groups
were comparable with respect to age, gender,
ethnicity, smoking history, sun exposure, height,
and
weight.
Approximately 80 percent of the enrolled
patients were Caucasian females, with only 3
African
Americans and 16 Hispanics in the Hylaform group.
Patient accountability, at the end of 12
weeks, of the original 133 patients, 123 patients
were
evaluated.
It should be noted that there were 130
patients who completed the 12 weeks. However, 7 of
the Hylaform patients did not have their IPR
scores
available at 12 weeks, and they were excluded.
Therefore, the actual follow‑up rate for
Hylaform was
92.4 percent and for Zyplast was 91.4 percent.
Of the patients who withdrew from this
part of the study and for the Hylaform group, two
patients were lost to follow‑up. One patient simply
wished to withdraw. In the Zyplast group, there were
two adverse events, and one patient just simply
wished
to withdraw.
Baseline wrinkle severity, the
investigators' live assessment at day zero showed
a
mean for the Hylaform of 3.5 and Zyplast of 3.6.
Remember, the inclusion criteria was a score of
three
or four on the six‑point scale. And the minimum and
maximum scores that were presented by the live
investigators were three to four.
The independent panel reviewers who looked
at the photographs taken at day zero had a mean
for
the Hylaform of 2.2. Zyplast was 2.3. And
based on
their scoring, patients from zero to five were
enrolled in the study.
The endpoint wrinkle severity, which was
at 12 weeks.
The mean for the Hylaform was 2.4, the
Zyplast 2.3.
Again, the minimum, maximum numbers are
at the bottom and the independent panel
reviewers'
scores at 12 weeks 2.3, 2.2 with the same ranges.
Adverse events, in the initial phase of
the study, we were presented 117 patients with at
least one adverse event, representing 88 percent
of
those patients enrolled in the Hylaform arm and a
similar percentage in the Zyplast arm.
It should be noted that there were 342
adverse events in those 117 patients and 322
adverse
events in the 112 Zyplast patients. The majority, as
you can see here, were procedure‑related.
If you look at the procedure‑related
adverse events, most of them fell within the
injection
site erythema or bruising, swelling, pain, and
pruritus.
And I think this was outlined nicely by the
sponsor in their presentation.
For the repeat phase, the same 96 patients
were enrolled on each side. Again, for the Hylaform
side, there were 269 adverse events in 87
patients,
286 adverse events in the 92 Hylaform Plus
patients
who had at least one adverse event. And, similar to
the initial phase, the adverse events were
generally
in the mild category of injection site
difficulties.
On the second repeat phase of the study,
the majority of the adverse events were noted on
patient diaries.
On the initial phase, it was by the
investigator during his office observations.
For the immunological response, serum IgG
levels during the repeat phase were determined to
evaluate the response to repeat treatments with
Hylaform.
There was no immunologic response
demonstrates.
That is, no patient had a fourfold
increase in the IgG levels during the repeat
treatment
phase.
Only one patient had an elevated serum IgG
level to four times the standard. And this was before
treatment.
At the end of this presentation, you will
be asked about the appropriateness of this
evaluation
to determine long‑term safety.
Duration of effect. This is the
12‑week
IPR baseline analysis of the percent of the
number of
patients who returned to baseline during this
study.
At two weeks, 38.2 percent of the Hylaform‑treated
patients returned to baseline; 2.9 percent of the
controls, the Zyplast group, did. At 4 weeks, 8
weeks, and at 12 weeks, 73.3 percent of the
patients
returned to baseline; 65.1 percent of the
patients
returned to baseline.
For the analysis of masking, this was
presented by the sponsor. Approximately 75 percent in
each group did not know to which treatment arm
they
were assigned.
The conclusions were that adverse events
were similar in both groups. And improvement of
wrinkle severity at 12 weeks was comparable.
At this point Ms. Phyllis Silverman will
come and review the statistical analysis.
STATISTICAL REVIEW
MS. SILVERMAN: Good
afternoon. I'm
Phyllis Silverman, the statistical reviewer for
this
PMA.
You have already been familiarized with
the sponsor's clinical study, claims, and multi‑phase
nature of this study. My task is to evaluate the
validity of the data presentation as well as
point out
the strengths and weaknesses of the study design
and
analyses.
Since claims for efficacy of repeat
treatments or of Hylaform Plus have been
deferred,
this review will focus on the initial phase
only. The
following is an outline of what I will
discuss. You
can glance at that quickly.
The sponsor's clinical study was
well‑designed and the PMA clearly written
and
comprehensive.
The use of the concurrent control and
multiple evaluators made for a strong study
design.
The study was designed as both a non‑inferiority
and
a superiority study with separate criteria for
each
one.
The six‑point Genzyme grading scale was
specifically created and validated for this
study. A
validation study performed on 46 photographs
rated
once and then again two weeks later by the same
three‑member independent review panel
resulted in an
inter‑rater correlation of .91 as measured
by the
kappa statistic and an intra‑rater
agreement between
the first and second readings of approximately 80
percent.
The use of photographic evaluations for
the independent review panel, hereafter referred
to as
the IPR, assisted in maintaining the blind. Patient
masking was also successful as determined by
querying
patients as to which treatment group they
believed
they had been assigned. And you have seen some of the
results of that from our clinical reviewer.
The two treatment groups were
well‑balanced on all demographic features,
which
included age, weight, height, gender, ethnicity,
smoking history, and sun exposure. Therefore, I
consider the randomization and the masking to
have
been effective.
Patient accountability was very good.
Of
the 261 patients randomized and treated, 255
completed
the 12 weeks of the initial study phase. Three
patients in each treatment group withdrew from
the
study and an additional 7 Hylaform and 8 Zyplast
patients did not have 12‑week IPR scores
and were
excluded from the primary efficacy analysis. Thus, it
was not a true intent‑to‑treat
analysis but close.
I have examined these 15 cases that did
not have 12‑week IPR scores. And these patients
appear to be missing at random. Thus, there is no
reason to suspect that any bias was introduced by
their exclusion.
The sponsor did not estimate any missing
values.
And there was no data imputation.
All
patients were included in the safety
analysis. The
per‑protocol subgroup consisted of 115
Hylaform and
109 Zyplast subjects.
The study was sized to test both
non‑inferiority and superiority. The sponsor
confirmed their estimate of the standard
deviation
from an external data collection on 32 Zyplast‑treated
patients over 12 weeks. This estimate was used to
calculate the sample size for the pivotal study.
It was calculated that 108 completed
patients for group would afford more than 80
percent
power for a non‑inferiority test with a
delta of
one‑half point on a 6‑point scale and
95 percent power
for a superiority test of one full point. Thus, the
study was sized adequately for efficacy.
The primary efficacy variable, which was
the mean of the median IPR scores ‑‑
and that was the
median of 3 evaluators ‑‑ at 12 weeks
was 2.3 for
Hylaform patients and 2.2 for Zyplast.
The lower bound of the one‑sided 97.5
percent confidence interval for the adjusted
difference was ‑.38, indicating that
Hylaform was less
than one‑half point inferior, thus
satisfying the
non‑inferiority criteria with a
significance level
equivalent to 2 and a half percent. The analysis was
done on the intent‑to‑treat
population and on a
per‑wrinkle basis.
To construct the confidence intervals, the
sponsor used a repeated measures analysis of
co‑variance model with the co‑variates
being treatment
group, site, patient within treatment group, and
baseline IPR score.
The patient scores for the right and left
nasolabial folds served as the repeated
measure. This
analysis was appropriate because it adjusted for
any
differences in baseline values and accounted for
the
within‑patient correlation between the two
sides of
the face.
Adjustment for baseline differences was
particularly important because patients were
entered
into the study based on a live wrinkle score of
three
or four, but the analysis was based on the more
variable IPR scores assessed from
photographs. The
superiority claim held to a higher threshold was
not
met.
The sponsor also performed a categorical
analysis comparing the proportion of patients who
maintained at least a one‑point improvement
in both
nasolabial folds at 12 weeks by the blinded
assessment.
This proportion was higher for Zyplast
than Hylaform, although not statistically
significant.
The investigator live wrinkle severity
score and the investigator and patient global
assessments were extremely close between Hylaform
and
Zyplast, generally within one‑tenth of a
point with,
again, no statistical difference.
As an aside, I would also like to point
out that results at earlier follow‑ups. That is, the
2, 4, and 8‑week follow‑up also
showed the same
consistent pattern as any of the 12‑week
endpoints.
The sponsor performed subgroup analyses
for the primary endpoint for the subgroups
defined by
smoking history and sun exposure. No significant
difference in median IPR scores between treatment
groups were noted based on smoking history or sun
exposure using a confidence interval
analysis. Thus,
it is acceptable to pool these subgroups for the
analysis.
As for pooling across the sites, the
sponsor provided a site‑by‑site
analysis of the
primary efficacy endpoint. The direction of the
difference, Zyplast minus Hylaform, was always
negative, indicating Zyplast did just a little
better
at each center.
However, what is important here is
that there was no treatment by site interaction
and
the data are poolable.
The analysis of the primary endpoint,
which was the median IPR score at 12 weeks, was
also
performed on the per‑protocol
population. Eighteen
Hylaform and 19 Zyplast patients were excluded
from
the per‑protocol analysis due to major
protocol
deviations, leaving 115 Hylaform and 109 Zyplast
subjects.
The mean of the median IPR scores were
identical to the intent‑to‑treat
population. And the
lower bound of the confidence interval for the
difference was ‑.36, a hair tighter than
the
intent‑to‑treat analysis. Thus, the non‑inferiority
criteria were met for the per‑protocol
population.
As far as safety is concerned, the
incidence of overall adverse events was identical
in
each treatment group and most were mild. The
occurrence of individual events appears to be
comparable in both groups.
Given the sample size, large
differences
would have been required between the treatment
groups
for any individual rate to be statistically
increased.
The study was not sized for this purpose. The safety
profile has been discussed by the clinical
reviewer
and should be evaluated from the clinical
perspective.
One area of concern is the fact that 94
percent of the subjects were women and 80 percent
of
the subjects were Caucasian. Although this
distribution is likely representative of the
target
population of people who would seek this
treatment in
real life, the 26 non‑Caucasian subjects
may not have
been sufficient to assess how Hylaform performs
in all
skin types, which can differ with respect to
scarring,
for example.
Therefore, this issue should be
evaluated from a clinical perspective.
My other concern is the longevity of the
treatment.
A comparison of duration of effect between
Hylaform and Zyplast was never a primary or
second
endpoint of this study. And no testing for
statistical significance was performed. However, I
think it is important to point out that over half
of
the Hylaform folds returned to their IPR baseline
by
four weeks and almost three‑quarters by 12
weeks.
Zyplast wrinkles did a little better,
particularly at the earlier time points. I will give
you a moment to study these numbers.
(Pause.)
MS. SILVERMAN: In summary, I
find that
the sponsor conducted a well‑designed and
analyzed
clinical study and that the data support the
non‑inferiority of Hylaform to Zyplast for
treatment
of nasolabial folds. The superiority of Hylaform was
not demonstrated. And the longevity of this treatment
should be evaluated from the clinical
perspective.
Thank you.
ACTING CHAIRPERSON CHANG: At
this time I
would like to ask panel members, are there any
questions that need to be directed to the FDA
presentation?
Dr. Blumenstein?
PANEL
DELIBERATIONS AND ADDRESS FDA QUESTIONS
MEMBER BLUMENSTEIN: I would like
to ask
the FDA if they believe that Zyplast was
effective in
this study.
DR. WITTEN: Yes. Well, I would just say
that we picked a control on the basis that we
could do
a comparison to an effective product at 12 weeks.
So our selection wasn't based on a
demonstration within this study or let's say
working
with the sponsor and accepting the control they
proposed wasn't based on a demonstration in the
study.
It was based on our understanding of the
performance
of the product use for the control. And its
performance is generally accepted in the clinical
community.
So it's not based on the study but based
on what we know about the control treatment.
MEMBER BLUMENSTEIN: Well, there
were two
slides presented by Dr. Lerner. One of them was the
baseline wrinkle severity table with the
independent
panel review.
The other was the endpoint wrinkle
severity by the independent panel review.
If I look in the Zyplast results there,
the mean baseline score for Zyplast is 2.3 by the
independent panel review and the mean score at 12
weeks by the independent panel review is
2.2. So that
the difference is .1.
DR. WITTEN: Well, can I just
clarify that
or perhaps I will ask Dr. Lerner to clarify my
clarification if I'm wrong. There is a baseline
assessment.
I'm just looking at the handouts, on page
4, which has the slides on it.
The independent panel review, day zero, is
that the post‑treatment assessment or the
pretreatment
assessment?
Is that the baseline post‑treatment
assessment?
DR. LERNER: That's the number
that was
given to the patients for inclusion into the
study.
So if you look at the investigators' live
assessment
at day zero, the 3.5 and 3.6 were the mean of all
of
the patients included into the study. That fell
within the inclusion criteria.
DR. WITTEN: And then the
independent
panel review assessment is?
DR. LERNER: That's the panel's
review of
the photographs taken at time‑zero before
treatment.
And then at 12 weeks, that's the endpoint.
MEMBER BLUMENSTEIN: So the
question is,
was Zyplast effective in this study for the
patients
treated with Zyplast? And the mean of 2.3 at baseline
and 2.2 at 12 weeks using comparable methodology
for
assessing the endpoint is a difference of .1 with
a
standard deviation of 1.04 and 1.12 for the
second.
I just happen to have a little computer program
that
lets me put this stuff in, which is not
significant.
MEMBER BARTOO: Excuse me. I am taking a
look at the slides. And baseline wrinkle severity
shows here 3.5 Hylaform at baseline.
MEMBER BLUMENSTEIN: That's a
different
methodology.
Live assessment is the investigator at
the clinical site. The next slide is independent
panel review.
MEMBER BARTOO: Right.
MEMBER BLUMENSTEIN: You might
also ask
the question why there is such a difference
between
the investigator at the clinical site and the
panel.
That is another issue. What I am trying to get at,
was Zyplast effective in this study?
DR. LERNER: The simple without
trying to
be funny answer is .1.
MEMBER BLUMENSTEIN: My
conclusion is that
it was not.
Therefore, the demonstration of
non‑inferiority is non‑inferiority to
something that
didn't work.
ACTING CHAIRPERSON CHANG: Dr.
LoCicero?
MEMBER LoCICERO: Again, not to
be trite,
but one of these four is not like the other. If one
looks at the initial live assessment, you get 3.5
and
3.6. The validated
from a previous study independent
panel review is 2.2 and 2.3.
The reason for entry was the live
assessment.
And the evaluation of efficacy was
independent assessment. The post‑study independent
assessment is 2.3 and 2.2, which is not different
from
the investigators' live assessment of 2.4 and
2.3.
So looking at those four panels, I would
have to assume that the investigators were
overaggressive in entry criteria. And if I'm wrong,
I'd like ‑‑
MEMBER BLUMENSTEIN: That would
be one
possible interpretation of why the investigators'
scores, the clinical site investigators' scores,
are
higher, was that they were ‑‑ the
word "fudging"
doesn't really ‑‑ that they were
inflating those
scores to be able to get the patients on the
study.
That would be one possible explanation.
The point is that I think the efficacy of
Zyplast in this study needs to be assessed using
comparable rating. And the sponsor went to a great
deal of trouble to set up the independent panel
review.
And they did take the photographs at
baseline, and they did get the scores at
baseline.
And they also looked at the scores at 12 weeks.
So my conclusion is that Zyplast was not
effective.
MEMBER BLUMENSTEIN: But the
point is
ACTING CHAIRPERSON CHANG: Dr.
Miller?
MEMBER MILLER: I guess I'm a
little
confused because I thought the baseline wrinkle
severity was the starting point after the
treatment
and that they don't like ‑‑ the
baseline wrinkle
severity is at pretreatment. And so at time‑zero,
immediately after treatment, we have no data on
that,
on what they looked like at the outset of the
trial
here?
MEMBER BLUMENSTEIN: Well, you
had some
two‑week data and some four‑week. I don't remember
the time.
I don't remember the time points.
MEMBER MILLER: Okay. I'll have to look
back at the data here.
ACTING CHAIRPERSON CHANG: I have
a
question to the sponsor, then, to try to clarify
this.
Dr. Blumenstein is saying that a live examination
of
the numbers does not match a pictorial evaluation
of
these same patients. Is that true or is the picture
at baseline after injection of these
materials? That
is the key question.
Pictures were taken of the patient at
point zero.
Was that after filler was injected to
start off a study or was that before any
treatment was
done?
DR. POLISSON: The pictures were
taken at
baseline before the patients were treated. Again,
that was the primary endpoint that we were
hanging our
hat on because we felt it was better with respect
to
blinding at the site, was much more systematic
and
objective to do so.
The live scores were done live with a
patient in the room at the time of
randomization. So
the two scores made. A couple of things I would like
to bring out about the live scores that have been
introduced to me by my colleagues.
If the panel allows, I am going to
actually ask that person to comment, but, first
of
all, the live scores we don't believe were a way
to
get patients randomized into this trial in an
overzealous manner because if you look at the
rate of
enrollment, this was a very, very popular study.
Patients were randomized in a very, very short
period
of time.
So it wasn't a gimmick to kind of get
patients in.
The other thing is that live scores
clearly represent different information. A live
score, I'm a rheumatologist. So I can take a look at
an X‑ray.
And I know that the information that you
get is much different than when it's digitized on
a
screen.
So it's a 3D, versus a 2D, effect.
We would like to say that the live scores
really changed and there was no difference
between the
two treatment groups throughout the course of the
study. So
I would like to clarify that.
Dr. Witten, would it be possible for me to
ask Dr. Monheit to amplify those or, Dr. Chang,
could
I ask one of our investigators to amplify that or
have
I answered your question?
ACTING CHAIRPERSON CHANG: This
does
answer that question that was posed and amplifies
what
Dr. Blumenstein is saying, that the data
presented
using the IPR shows change from 2.3 to 2.2. Thank you
very much.
MEMBER BARTOO: Can I ask another
question
regarding that?
ACTING CHAIRPERSON CHANG: Yes.
MEMBER BARTOO: For the live
scores, was
that blinded or unblinded in terms of the person
who
assessed that score?
MS. SILVERMAN: They were
unblinded.
MEMBER BARTOO: Unblinded.
ACTING CHAIRPERSON CHANG: Any
other
questions for FDA? Dr. LoCicero?
MEMBER LoCICERO: I just want to
clarify
from Dr. Lerner.
The entry criteria was the live
score and the evaluation after 12 weeks was the
independent panel?
DR. LERNER: Yes, that's correct.
ACTING CHAIRPERSON CHANG: It's
time to
move on to the FDA questions. May we have the
questions on the screen, please? Question, Dr.
Halsey?
MEMBER HALSEY: I'm still
concerned about
the avian protein dose and that it might be
significant and want to be sure that I haven't
made an
error in my calculations.
The data that I have in this submission
says that that's .4 percent, which would be if
this is
correct, 4 parts per thousand. So it's possible that
the avian dose that the patient gets could be
significant.
DR. BURNS: Can I?
ACTING CHAIRPERSON CHANG: Dr.
Burns?
DR. BURNS: Yes.
MEMBER HALSEY: Go ahead and
answer that.
DR. BURNS: I want to make sure I am
looking at the same thing that you are. This is .4
percent with a range of .12 to .85 weight
percent?
MEMBER HALSEY: That's correct.
DR. BURNS: That's for Hylan A,
which is
an intermediate for the final production of Hylan
B.
MEMBER HALSEY: Okay.
DR. BURNS: The final product,
Hylaform,
has a product spec of .052 milligrams per
ml. And
over a series of 89 lots, the actual number comes
out
to approximately 10 milligrams per ml, which I
believe
is about 10 parts per million.
MEMBER HALSEY: .05 milligrams
per ml.
DR. BURNS: That's the spec. And over a
series of approximately 89 lots, it comes out to
.01
mgs per ml.
MEMBER HALSEY: So we're down to micrograms
of dose.
DR. BURNS: Right, approximately
ten parts
per million.
MEMBER HALSEY: That is a step
forward.
And that may be good enough, but I think that
still
was a question.
The other question I have on safety is
that the duration of the study was fairly short,
as I
recall, for both antibody measurements and any
other
assay for delayed type hypersensitivity, which
was not
done.
In view of the fact that, as I could
determine it from what was presented, we didn't
know
if the assay measured IgG because it seemed to
measure
other isotypes of immunoglobulins and there was
no
inhibition done, so we don't know if we were
measuring
antibody to what we were measuring antibody
to. So I
think we don't know enough about the immune
response.
Finally, I would ask, what are the
exclusion criteria that are used for the
treatment
with the collagen? Is a skin test or is an allergy to
bovine protein a requirement for the use of that
drug?
Can somebody tell me?
ACTING CHAIRPERSON CHANG: Dr.
Olding,
you're nodding?
MEMBER OLDING: Yes, it is one
test one
time.
Although I believe it is suggested to have two,
it is a requirement to have a skin test and then
that
be evaluated for a full month.
MEMBER HALSEY: Then I think we
should
discuss whether that would be a requirement here
for
avian protein sensitivity since one study
interval for
sensitization was relatively short and even
though
there's less than what we were concerned with
before,
there's still a significant dose of avian
protein.
DR. KINGMA: Wytske Kingma. I would like
to address the concern that you have with regards
to
duration of adverse events and sensitivity.
We really specifically looked at local
reactions in order to see whether there was
prolonged
effect.
When you look at the patient, entire patient
population, treatment emergence, not going into
whether they were procedure‑related or
whatever, to
look at everything, in effect, the majority of
the
events actually occurred within the first week
and
resolved within the first week.
That is equally the case in the first
initial phase of the study as well as in the
repeat.
In fact, there were only two patients in the
initial
phase that continued to have an event after 30
days,
which were induration and erythema, and the other
one
patient in the repeat treatment, which continued
to
have one event after 30 days.
So the delayed hypersensitivity is really
not in issue.
However, of course, as with any
thorough follow‑up with all adverse events,
we
continue to follow anything that may be ongoing.
In effect, if you look at the design of
the trial, you have the 12 weeks of the initial
phase.
Then you have a break where anything ongoing
would be
requirement of study design continue to be
followed.
In patients, the interval between initial
phase and repeat phase varies between 6 days and
152
days.
Then they went into the repeat, which continues
to be followed for another 12 weeks.
So if you look at it from the safety side,
you probably have a good expansion of about six
months
to eight months at least of safety data.
MEMBER HALSEY: For the patients
included
in this trial.
And you excluded those that might have
allergy to egg protein, correct? You've shown the
safety in this population, which is good, but we
haven't tested those. You have eliminated those from
the study population. So I am wondering if we
shouldn't require somehow that patients be tested
before they're treated.
DR. KINGMA: If you look at the
worldwide
experience, we have treated a lot of patients,
more
than 500,000 patients, with this product
specifically.
And there's no exclusion of such. And it has not been
a link.
There is no skin test that would tell you
whether or not an avian sensitivity will actually
predict a reaction.
MEMBER HALSEY: I hadn't seen
that data.
ACTING CHAIRPERSON CHANG: Do we
want to
have a discussion again about whether there is
reasonable ‑‑
DR. KINGMA: I think ‑‑
ACTING CHAIRPERSON CHANG: Excuse
me.
This is a discussion among the panel. I am asking for
a discussion among panel members to answer the FDA
question of available data presented in this PMA,
whether there is reasonable assurance that the
device
is safe.
Dr. Miller?
MEMBER MILLER: I think it's a
little
difficult, especially because of the questions
raised
about the avian protein issue. I think if you look at
the data that's been presented and compare it to
Zyplast, all the complications appear local.
And I can't I guess speak as competently
about the IgG levels after just four weeks if
that's
adequate.
It doesn't seem to be any significant
immune responses to the material, but it is a
select
population.
This population is a selected group to
exclude those who have a history of reacting to
foreign proteins.
So this just raises a question in my mind,
which it would be helpful to know worldwide data
perhaps or to look at what happens if you have
somebody you know has an allergy to avian protein
in
whom you inject this or perhaps to know what
happens
with that.
This is very similar I think to another
product for treating arthritis, I think. So what is
the experience in that group? Is there a restriction
in arthritis patients for those who have
allergies who
have avian proteins? And do they get this material
and not have a problem?
ACTING CHAIRPERSON CHANG: The
question
that you ask, Dr. Miller, may also be addressed
as a
query to FDA regarding labeling issues, warning
as an
example of trying to find some answers.
So FDA is asking at this time based on the
presentation given by the sponsor and by FDA's
evaluation and summation, based on examining this
data
today, opinions regarding reasonable assurance
that
this product is safe. So panel members are asked to
speak up in part of this discussion. Dr. Newburger?
MEMBER NEWBURGER: I think the
data show
that the product is safe, but I think it only
shows
that it's safe for one treatment. I don't see
anything else to speak to that to see that there
is
safety established for multiple treatments over
time.
But for the data presented, I think that it's
safe.
ACTING CHAIRPERSON CHANG: Yes?
MEMBER OLDING: I just want to
clarify
something.
You said there is no test for avian
allergy, no skin test? Is that correct?
MEMBER HALSEY: There is.
MEMBER OLDING: I thought I heard
her say
there was not.
ACTING CHAIRPERSON CHANG: Dr.
Halsey?
MEMBER HALSEY: Most definitely
there is.
Allergists do it all the time.
MEMBER DOULL: I might just comment
about
the tox part of the safety. The tox studies did
include, of course, subchronic. And they included
carcinogenicity studies.
So there was a repeated evaluation of the
hazard associated with toxicity. It's the immunology
part where they don't really have that well‑done.
But, as Dr. Krause told us, the full
battery of protocols required by the agency were
carried out.
And there were no toxicity alerts in any
of those studies which would raise serious
concerns
about the safety of the product from a tox point
of
view.
MEMBER HALSEY: Can I comment?
ACTING CHAIRPERSON CHANG: Yes.
MEMBER HALSEY: I think the
question of
egg allergy is a difficult one and the agency is
going
to have to decide if they're going to let a
primary
care physician and a patient decide if they are
allergic to egg protein or they're going to
require a
skin test.
There are reagents, licensed products for
doing that or there is a blood test that's
available
that people use throughout the world for such
determinations.
ACTING CHAIRPERSON CHANG: Dr.
Witten,
finally, the discussion of question 1 regarding
the
safety issue, one panel member stated the belief
that
comparing short‑term and local reactions
that this
product as a result of the PMA is deemed
safe. The
remaining issue is longer‑term study and
whether or
not because the PMA specifically excluded by
history
those who may have avian product hypersensitivity
that
the issue raised and question raised for labeling
perhaps is whether or not skin testing should be
recommended, suggested, or required as a
condition for
use of this product.
Does this answer the FDA's question to the
panel?
DR. WITTEN: Yes. Thank you.
ACTING CHAIRPERSON CHANG: May we
have
question 2, please? Question 2 is asking the panel to
discuss whether on the basis of this PMA the
device is
effective.
And we're open to comments. Dr.
LoCicero?
MEMBER LoCICERO: I think if we
work
backwards, the investigators at the endpoint
found,
both on live and independent panel, that there
was no
difference between the two groups following
completion
of treatment and 12 weeks of observation.
Another fact is that looking at the IPR
scores at the end of 12 weeks among patients who
received touch‑up had scores that were
within .5 of
the initial evaluation by the live group so that
touch‑up appears not to be affected in
changing from
baseline, nor are they different from one
another.
There is some difference in the initial
evaluation of patients between independent panel
review and the live review. I think the only way to
solve that is to know is there a statistical
difference between the live assessment and the
independent panel review. We don't have that data.
Finally, there is no data on African
Americans that is sufficient in any amount for us
to
assess its efficacy in that group.
ACTING CHAIRPERSON CHANG: Dr.
Blumenstein?
MEMBER BLUMENSTEIN: The sponsor has shown
non‑inferiority to Zyplast based on the 12‑week
measurement.
Unfortunately, Zyplast based on the
sponsor's own independent panel review has not
been
shown to be effective in this study based on the
data
that were shown to us here unless there is some
reason
to believe that Zyplast is effective in this
study and
one can conclude that the sponsor has shown
non‑inferiority to something that isn't
effective and,
therefore, as a result, this product is not
effective.
ACTING CHAIRPERSON CHANG: Any
further
comments?
Dr. Miller?
MEMBER MILLER: I guess I agree
with what
you say.
I mean, you're exactly logically correct in
what we have seen in the data today. However, I am
not sure how to factor in just the years of
experience
where Zyplast has been used to correct these
problems
with an effectiveness that is sufficient to
warrant
its continued use, maybe not demonstrated in a
rigorous fashion like we would like.
But certainly I guess I came into this
assuming Zyplast was effective because of the
experience of many years of its use in observing
how
it helped some patients. So to question the validity
of Zyplast is a sudden sort of a question to
raise.
I guess I am just having some trouble with that.
I know based on the data, you're exactly
right; the data we see here, you're exactly
correct.
I can't argue with you. But this data isn't really
exhaustive for what the experience has been with
Zyplast.
ACTING CHAIRPERSON CHANG: Dr.
Bartoo? I
would like to ask Dr. Olding also since it has
been
established that he has been a user of some of
these
products.
MEMBER BARTOO: I have to echo
some of the
comments from Dr. Miller. In addition, I know that
the sponsor has worked with FDA, as Dr. Witten
said,
to determine what is the appropriate
control. They
were told that Zyplast would be an appropriate
control.
I feel that to be fair to the sponsor,
they followed the directions from FDA as to what
they
should use for their control. So I think we need to
take that into consideration, in addition to the
fact
that Zyplast has already been shown to be
effective in
other studies and in its long‑term use.
ACTING CHAIRPERSON CHANG: Dr
Olding,
comment for the FDA regarding efficacy?
MEMBER OLDING: Certainly. I cannot fault
the statistical analysis of the data. However, two
comments.
Number one, I agree with Dr. Miller.
Certainly having utilized the products, there is
an
efficacy associated with them. The length of that
efficacy has certainly been long enough to have
been
approved by the FDA at some point in the past.
However, as in the last panel on
Restylane, when we discussed the superiority of
Restylane over the Zyplast, there was no
scientific
evidence that, in fact, it was better. And so the
panel has voted not to allow inclusion of
material in
the handout that says that it's superior in the
same
fashion.
This does not show any effect ultimately.
So based on a gut reaction, I think it has
to, but based on science, it apparently does not.
ACTING CHAIRPERSON CHANG: Not to
pick on
plastic surgeons, but I will ask Dr. Boykin to
weigh
in to ask about efficacy.
MEMBER BOYKIN: I think the
numbers just
underscore the difficulty of doing these types of
tests or demonstrating valid clinical results in
terms
of mathematical models. I think what is obvious is
that we have shown that there is quite a bit of
similarity between these two products. The efficacy,
of course, is different to different people. It
certainly isn't superior.
I do question the follow‑up evaluation.
It's hard to believe that it's unchanged
significantly.
But we have to deal with the data that
we have in order to make these decisions.
And without pulling in a lot of other
outside bias, I think it's safe to say that
perhaps
only half of the indications have been met and
that we
are lacking in some firm objective data to make
more
statements than that.
ACTING CHAIRPERSON CHANG: Dr.
Newburger,
is this an efficacious product?
MEMBER NEWBURGER: If it's
equivalent, if
this product performs essentially the same as
Zyplast,
my experience with several thousand times
injecting,
that product has efficacy.
ACTING CHAIRPERSON CHANG: Any
other panel
members with an opinion?
(No response.)
ACTING CHAIRPERSON CHANG: Dr.
Witten,
after discussion for question number 2 regarding
the
efficacy of the device proposed by sponsor, there
is
a divided opinion in terms of the data that has
been
presented.
There is a question in terms of efficacy
of primarily the control. The sponsor has shown that
there is no difference between the two, but the
question again is raised regarding the presumed
gold
standard of using collagen.
So looking at data, some members feel very
strongly that data has not shown the efficacy of
the
control itself; whereas, it is a different
mindset of
having that presumption of a gold standard being
efficacious having been approved and used for
many
years of not showing a change by the data
presented
today.
On the other hand, there is a strength of
clinical experience, including clinical
experience by
members of the panel, that yes, long‑term
clinical use
has shown its efficacy and, therefore, we have a
divided opinion regarding the efficacy of the
device.
Does this adequately answer your question?
DR. WITTEN: Yes. Thank you.
ACTING CHAIRPERSON CHANG: Question number
three, please?
Due to the low numbers of African
American patients that were enrolled in this PMA,
FDA
would like the panel members to consider this
question, should the device be approved? Should
sponsor be required to conduct a post‑approval
study
to collect safety data on specific
minorities? Is
there specific labeling that is needed to address
the
potential use in minorities or, I will say,
patients
of color?
Dr. Boykin?
MEMBER BOYKIN: Yes. I believe that a
post‑approval study would definitely be
indicated.
And safety data is certainly needed in this
particular
area.
I believe that the patients of color
present with issues that would require that they
be
looked at perhaps with some other outlines and in
respect to the safety of the device.
The labeling, of course, needs to be
reflective as well.
ACTING CHAIRPERSON CHANG: Dr.
Miller?
MEMBER MILLER: I agree with
that. I
would suggest that the exact same concerns arise
over
this as did this morning over the Restylane and
should
have sort of a parallel approach.
ACTING CHAIRPERSON CHANG: Dr.
Witten, in
answer to question 3, it's yes to both for the
previous discussions.
Does this adequately answer?
DR. WITTEN: Yes. Thank you.
ACTING CHAIRPERSON CHANG:
Question number
4 is sponsor proposes indications that
"Hylaform is
intended for the correction of soft tissue
contour
deficiencies, such as wrinkles and acne
scars." Based
on the fact that only nasolabial folds were
treated in
this PMA, has the information presented today
been
adequate to accept the scope as proposed by the
sponsor, to include acne scars? Dr. Newburger?
MEMBER NEWBURGER: I believe that
the
indications should hold as they're written. It's a
fairly short‑lived correction, so my
concern about if
there is cosmetic mistake in injection, that it's
not
going to have a long‑term adverse impact on
the
individual.
Also, there's the worldwide experience as
well where it has been used in this regard.
ACTING CHAIRPERSON CHANG:
Further
comment?
Dr. Olding?
MEMBER OLDING: Since we didn't
show that
Restylane theoretically lasts longer than Zyplast
from
the other panel, then to me your comments are not
consistent because this one only lasts a short
period
of time theoretically; i.e., the same as the
Zyplast.
And the other study did not show, the Restylane
did
not show, that it lasted longer. Therefore, it's hard
for me to understand that rationale.
In fact, there was one patient that
developed an aseptic abscess with this
particular. So
I'm trying to bring all of this so that it's
equal and
understandable?
MEMBER NEWBURGER: May I
respond? Your
point is well‑taken, but this, the
consistency of this
material, is different and the injection
technique is
different than the other material, I believe
because
there's a difference in the cohesiveness of the
substance, at least as I can glean from the
literature.
It's not going to have quite the same
visibility.
ACTING CHAIRPERSON CHANG: Dr.
Witten?
DR. WITTEN: Yes. I just want to comment
that we really need to stay away from discussing
the
product that was discussed this morning and focus
on
this application and this product and what we are
doing with this product.
ACTING CHAIRPERSON CHANG: Thank
you.
Comments that would relate to the use,
indications?
I would say the analogy would be soft
tissue defects, to say soft tissue defects. And would
acne scars be categorized as a soft tissue
defect?
MEMBER NEWBURGER: Sure.
ACTING CHAIRPERSON CHANG: Dr.
Newburger
says yes.
Any other comments? Dr. Witten?
MEMBER OLDING: Excuse me.
ACTING CHAIRPERSON CHANG: Yes?
MEMBER OLDING: I have one other
suggestion or question about this. Many of my
patients want to have augmentation of the
lips. The
lips I think if not new, it's one of the most
frequently requested areas for augmentation. There's
nothing in this particular guidelines that
they're
planning to distribute about its efficacy for
lips.
I would like to see in the guidelines for
their use that it has not been officially tested
for
lip augmentation. There's no clinical evidence of its
efficacy or its safety in lip augmentation.
ACTING CHAIRPERSON CHANG: Please
keep
that in mind.
That would be certainly an item that
would need to be brought up regarding potential
conditions for approval.
Dr. Witten, based on the discussion, panel
members believe that the indications are for soft
tissue defects, that acne scars would be rated
under
the category of soft tissue defects.
DR. WITTEN: Thank you.
ACTING CHAIRPERSON CHANG:
Question number
5. This
is the last question posed to the panel.
No
significant changes in adverse events were noted.
Does this data support the safety of the device
for
repeated use or do you believe that a post‑approval
study is needed to address this issue?
MEMBER HALSEY: I think we
discussed that
at the top in immunology earlier.
ACTING CHAIRPERSON CHANG: Can
you restate
your opinion, then?
MEMBER HALSEY: We discussed this
earlier
and felt that it is possible that the avian
protein
dose might be significant, even though it's in
the 10
to 20 microgram range, and that the duration of
the
immunology studies was limited. And the question of
an exclusion criteria for patients that receive
this
treatment is something I think the agency needs
to
consider since the studies were short‑term
and not
complete.
ACTING CHAIRPERSON CHANG: Any
other
discussion?
(No response.)
ACTING CHAIRPERSON CHANG: Dr.
Witten, as
previously discussed in conjunction with the
first
question, it is felt that there has been limited
12‑week study for immunological
reactions. And,
therefore, post‑approval studies should be
considered
to address this issue.
DR. WITTEN:
Thank you.
ACTING CHAIRPERSON CHANG: We're
going to
proceed now with the next open comment
session. At
this time no one has notified the FDA that they
wish
to address the panel with open public comment,
but I
will ask the audience if there is anyone who
wishes to
address the panel for approximately five minutes
regarding the issues that have been discussed
this
afternoon.
(No response.)
ACTING CHAIRPERSON CHANG: I see
no
raising of hands. At this time, is there any FDA
summation?
DR. WITTEN: FDA has no further
discussion.
ACTING CHAIRPERSON CHANG: Thank
you, Dr.
Witten.
Is there an applicant summation by Genzyme
Corporation?
DR. POLISSON: Thank you, Dr.
Witten.
SPONSOR
SUMMATION, CONCLUDING PANEL DELIBERATIONS
AND VOTE
DR. POLISSON: Dr. Witten and
panel
members, thank you for the chance to provide a
summary
and to provide some rebuttal to some of the
points
that were made in the last period of discussion.
The first thing I would like to talk about
is the safety issue. I would just like to remind the
panel that Hylan B, of course, which is made from
hyaluronic acid in preclinical studies, has been
shown
in our application to be safe, nontoxic, and
non‑immunogenic and that we feel in our
study that the
safety of Hylaform was comparable to that that
was
observed in Zyplast and, in addition, in the
repeat
treatment phase that Hylaform appears to be safe
and
particular for that one patient. There was no
association between IgG titers and adverse
events.
I think I would like to focus now on the
last two bullets. And that is the worldwide
post‑market adverse event rate is about .11
percent.
We all recognize how these figures are obtained
in a
pharmacovigilance post‑marketing setting,
but I would
also like to add a few other points.
In our worldwide label for both Hylaform
and Synvisc, which is used for the treatment of
osteoarthritis, we do have a cautionary phrase
for
patients who have allergies to avian
proteins. We
would clearly expect to see this in our label in
the
U.S.
I just also would like to remind people in
terms of volume of exposure that nine million
units of
Synvisc have been sold worldwide to date and,
finally,
that there has been no skin test that has been
required for use pre‑exposure to this
particular
treatment.
A lot has been made of efficacy.
And we
have heard questions about, does this really work. It
actually resonates with me, the comment that
Zyplast
really does work because it's been out for two
decades.
I would like to remind the panel that the
Zyplast has never been tested like we have tested
it
in this trial.
It's never been tested in an IPR type
of review.
So I think that I believe that for the
purposes of this study, that we have met our
primary
endpoint as agreed to with the colleagues at FDA.
Really, finally, to really fully evaluate
in my opinion Zyplast, does it really work, one
would
have to add a placebo control group to this,
which we
would obviously be unable to do because of
efficacy
issues.
The point under there I have beaten to
death is that we feel that we have really
developed a
robust endpoint and that, again, Zyplast has
never
been tested to that.
A couple of other points here that I want
to make are that we have met our primary
endpoint, but
if there is an insecurity about the primary
endpoint,
what I have always been taught ‑‑ and
my clinical
trial, of course, as one looks to the totality of
the
evidence and one looks to secondary efficacy
endpoints, I will remind the panel that the
patient
and physical live and the globals were all better
at
12 weeks and were comparable to that seen with
the
Zyplast.
On average, patients and physicians
continued to assess response to treatments as
better
or much better at 12 weeks. And I believe the figures
are 66 percent for patients and 83 percent for
physicians.
And, again, that is comparable to
Zyplast.
So I really do feel that not only from a
statistical point of view but from a clinical
point of
view, that we have met our endpoint and this is,
in
fact, effective.
A few of the things that Dr. Monheit
wanted to get to the podium to describe for you
is
that we really limited touch‑ups in this
study. And
this does not necessarily reflect practice. Touch‑ups
in other studies and in practice really are done
to
produce optimum correction.
We reduced or limited touch‑ups to one
touch‑up only. And the reason that we did that was
that we wanted to reduce the variability in the
study.
We didn't want to have three or four touch‑ups
in one
treatment group and have to try to answer that in
our
analysis at the end.
Again, the final thing is and I am sure
that it has not escaped you is that Hylaform was
similar to Zyplast in this trial with less volume
injected.
Next. I just want to point out
one thing
here.
Most of the stuff I have already alluded to.
But in terms of duration of effect, I've heard
some
talk about the treatment worked, and then it lost
its
effect early on.
This study again was not designed to be a
study in which we evaluate duration of effect of
time
to treatment failure. This was designed to look at
the comparability between Zyplast and Hylaform at
12
weeks in a non‑inferiority paragon. And we met that
endpoint.
And so, again, in the last bullet there,
I think most of the people who have taught me
statistics tell me that multiple post hoc looks
at
this at four weeks and eight weeks really are
statistically problematic.
Next. A final point about this,
not so
much the duration of effect, but it works back to
the
efficacy issue, is the nasolabial fold, as I
mentioned, I believe, is the worst case, as my
colleagues have been teaching me, and that the
duration of correction might be expected to be
shorter
than in other locations with previously studied
fillers.
I think there are a lot of caveats.
There
is a lot of stuff around this trial that just
goes
beyond the statistical that I believe should be
taken
into consideration, the least of which is
previously
clinical studies and post‑market
experience.
Next. Now with respect to skin
types, we
have heard a lot this afternoon regarding the
lack of
exposure of patients of color to this particular
intervention.
I will remind the group that 20 percent
of the study population was people of color. It was
comparable efficacy between those two groups,
comparable safety profile, and no occurrences of
hypertrophic scars, or keloid formation and no
hyper
or hypopigmentation.
Dr. Holmdahl pointed up that the ethnic
makeup reflected the target population. And, finally,
I believe that Inamed, who is our partner in this
regard, has 20 years of successful experience in
dealing with dermal fillers in diverse
populations.
Finally, Hylaform is a clear gel.
It's
not opaque.
And it might be expected to be neutral
with respect to implantation in people of color.
Next slide. Many different types
of
wrinkles have been tested in the U.S. and the
Swedish
study that I presented in my part of the
presentation.
We have focused on the nasolabial fold.
Again, we did that for a particular
reason.
And so if we think that we're not inferior to
Zyplast, we would expect that the degree of
correction
would be equivalent in other areas and equivalent
to
how Zyplast works in practice.
Finally, with repeat treatment, our
feeling is that we did this primarily to look at
repeat exposure.
So, again, patients who had been
randomized to the Hylaform arm at 12 weeks were
asked
whether or not they wanted to re‑enroll in
the repeat
treatment phase.
And we have significant safety data
at four weeks after repeat treatment.
Again, the majority of these adverse
events are likely to occur in the first
week. And,
therefore, no further study is indicated at this
time
in our opinion.
And with repeat treatment, we saw no
increased safety issues and, most importantly to
me,
I believe that we have defined no association
between
IgG antibody titers to Hylan B and the adverse
event.
Then I think my final slide has to do with
the skin tests and that I believe that there have
been
a number of people who were at the podium today,
Dr.
DeLustro in particular, who have suggested that
skin
testing is not predictive of clinical reaction.
HA, again, is biogenetically conserved.
It's not a different protein across all species.
Going back to our Synvisc experience, it's been
used
worldwide without a skin test. We don't think it's
immunogenic.
Based on this data and the literature,
we do not believe that a skin test pre‑exposure
for
Hylaform is indicated.
Thank you for your attention.
ACTING CHAIRPERSON CHANG: Thank
you.
At this time I am going to ask Dr. Krause
to read the voting instructions for the panel.
EXECUTIVE SECRETARY KRAUSE:
"The medical
device amendments to the Food, Drug, and Cosmetic
Act
as amended by the Safe Medical Devices Act of
1990
allows for the Food and Drug Administration to
obtain
a recommendation from an expert advisory panel on
designated medical device pre‑market
approval
applications that are filed with the agency.
"The PMA must stand on its own merits.
And your recommendation must be supported by
safety
and effectiveness data in the application or by
applicable publicly available information.
"Safety is defined in the act as
reasonable assurance based on valid scientific
evidence that the probable benefits to health
under
conditions on intended use outweigh any probable
risks.
"Effectiveness is defined as reasonable
assurance that in a significant portion of the
population, the use of the device for its
intended use
and conditions of use when labeled will provide
clinically significant results.
"Your recommendation options for the vote
are as follows.
Number one, approval. This is if
there are no conditions attached. Number two,
approvable with conditions. The panel may recommend
that the PMA be found approvable subject to
specified
conditions, such as physician or patient
education,
labeling changes, or a further analysis of the
existing data.
Prior to voting, all of the conditions
should be discussed by the panel.
"Number three is not approvable.
The
panel may recommend that the PMA is not
approvable if
the data do not provide a reasonable assurance
that
the device is safe or if a reasonable assurance
has
not been given that the device is effective under
the
conditions of use prescribed, recommended, or
suggested in the proposed labeling.
"Following the voting, the Chair will ask
each panel member to present a brief statement
outlining the reasons for their vote."
ACTING CHAIRPERSON CHANG: I will
entertain a motion. Dr. LoCicero?
MEMBER LoCICERO: I move non‑approval
until the FDA can clarify issues within the PMA,
specifically this issue concerning the
variability
between the live evaluation and independent
evaluation.
MEMBER BLUMENSTEIN: I second it.
ACTING CHAIRPERSON CHANG:
Discussion?
(No response.)
ACTING CHAIRPERSON CHANG:
Hearing no
discussion, I am going to ask the panel members
to
raise their hand if they vote yea, non‑approval. Call
for any years?
(Whereupon, there was a show of hands.)
ACTING CHAIRPERSON CHANG: Dr.
Blumenstein, Dr. LoCicero, Dr. Boykin, Dr.
Diegelmann.
No to the motion?
(Whereupon, there was a show of hands.)
ACTING CHAIRPERSON CHANG: Dr.
Halsey, Dr.
Miller, Dr. Newburger, Dr. Olding, Dr. Doull.
The motion is defeated. I will
entertain
another motion.
There were no abstentions. The
motion for non‑approval has been
defeated. And I will
entertain another motion. Dr. Halsey?
MEMBER HALSEY: I move that the
product be
approved with conditions.
MEMBER OLDING: Second.
ACTING CHAIRPERSON CHANG: Second
by Dr.
Olding.
Open the floor to discuss and the
recommendation for such possible PMA approval
with
conditions.
Dr. Halsey?
MEMBER HALSEY: I would ask the
agency to
require some assessment of avian protein allergy
in
patients before they are treated. And I am not
specifying what that need be. It could be decided
later with the agency's consultants.
ACTING CHAIRPERSON CHANG: Again,
just to
repeat that again, you would ask as a condition
that
the sponsor ask or ‑‑
MEMBER HALSEY: That the directions for the
use of the treatment be limited to those that
pass an
assessment of allergy; in other words, that are
not
allergic to the drug.
ACTING CHAIRPERSON CHANG: Could
I suggest
an assessment of possible hypersensitivity to
avian
products?
Is that your intent?
MEMBER HALSEY: To avian products, yes.
ACTING CHAIRPERSON CHANG: Is
there a
second to this condition?
MEMBER MILLER: I just have a
question
about your proposal. Are you suggesting that we
require a test or as a simple screening people
for
those who deny a history of sensitivity to avian
products?
Is that adequate?
MEMBER HALSEY: I decided we
should give
the FDA some latitude to develop a policy on
that. It
could be historical, as was done in the clinical
trial, or it could be a blood test or it could be
a
skin test of avian proteins. I would like to not have
to specify at this time.
MEMBER MILLER: I'll second that.
ACTING CHAIRPERSON CHANG:
Seconded by Dr.
Miller.
Comments, please?
(No response.)
ACTING CHAIRPERSON CHANG: I
would like a
show of hands.
The proposed condition states that the
sponsor as a condition of approval of this PMA,
that
there be some assessment of potential of
hypersensitivity reaction to avian products. May I
have a show of hands for those who would vote yes
for
this proposed condition?
(Whereupon, there was a show of hands.)
ACTING CHAIRPERSON CHANG: Dr.
Halsey, Dr.
Diegelmann, Dr. Newburger, Dr. Miller.
May I have by a show of hands those who
would say no to imposing this condition? All votes
for no?
(No response.)
ACTING CHAIRPERSON CHANG: May I
ask those
who have abstained to please raise your hand?
(Whereupon, there was a show of hands.)
ACTING CHAIRPERSON CHANG: Dr.
Olding, Dr.
Doull, Dr. Blumenstein, Dr. Boykin, Dr. LoCicero.
Motion passes. So this one
condition is
an assessment for hypersensitivity to avian
products.
Dr. Miller?
MEMBER MILLER: I would like to
move for
three additional conditions.
ACTING CHAIRPERSON CHANG: Can we
just do
one at a time, please? You are certainly welcome to
bring one up.
And we will discuss and move on, then.
MEMBER MILLER: I would propose
that we
have an assurance of a physician qualification
and
education prior to use of this product as a
condition.
ACTING CHAIRPERSON CHANG: The
motion is
that physician education be incorporated as a
condition for approval. Is there a second?
MEMBER NEWBURGER: Seconded.
ACTING CHAIRPERSON CHANG:
Seconded by Dr.
Newburger.
Comments?
(No response.)
ACTING CHAIRPERSON CHANG: May I
have a
show of hands, please, for those who would accept
this
proposal as a condition?
(Whereupon, there was a show of hands.)
ACTING CHAIRPERSON CHANG: Dr.
Olding, Dr.
Doull, Dr. Halsey, Dr. Newburger, Dr. Miller.
By show of hands, those who would vote no
for this condition?
(No response.)
ACTING CHAIRPERSON CHANG: Please
by a
show of hands, those who would abstain from this
condition?
(Whereupon, there was a show of hands.)
ACTING CHAIRPERSON CHANG: Dr.
Blumenstein, Dr. Boykin, Dr. Diegelmann, Dr.
LoCicero.
Five.
The motion passes to incorporate physician
education as a potential condition for PMA
approval.
Further comments or recommendations?
Dr.
Miller, did you have a second condition you had
in
mind?
MEMBER MILLER: Yes. I think that the
labeling needs to state that its use in people of
color if I could just say similar to the one we
suggested this morning. I don't remember the words,
but I liked the words.
MEMBER OLDING: I could read it
if you
want it.
MEMBER MILLER: Could you,
please? Thank
you.
MEMBER OLDING: "Limited controlled
clinical study data are available regarding the
use of
Hylaform in patients with skin types V and VI on
the
Fitzpatrick scale and individuals of color"
or "people
of color."
ACTING CHAIRPERSON CHANG: Do I
have a
second to this motion?
MEMBER OLDING: I'll second it.
ACTING CHAIRPERSON CHANG: Dr.
Olding
seconds.
Is there a discussion?
(No response.)
ACTING CHAIRPERSON CHANG:
Hearing none,
I would like those who would be in favor of this
proposed condition to state in the labeling that
there
is limited controlled clinical data available for
use
of this device for persons of color or those in
the
Fitzpatrick V or VI category. All of those in favor,
please raise your hands.
(Whereupon, there was a show of hands.)
ACTING CHAIRPERSON CHANG: Dr.
Olding, Dr.
Doull, Dr. Halsey, Dr. Diegelmann, Dr. Newburger,
Dr.
Miller.
Opposed?
(No response.)
ACTING CHAIRPERSON CHANG: Those
abstaining, please raise your hands?
(Whereupon, there was a show of hands.)
ACTING CHAIRPERSON CHANG: Dr.
Blumenstein, Dr. Boykin, Dr. LoCicero.
Motion passes.
Dr. Miller?
MEMBER MILLER: I would like to
move that
there also be a post‑approval study
involving people
of color to assess the efficacy and safety in
that
population.
MEMBER NEWBURGER: I second that.
ACTING CHAIRPERSON CHANG: And
again?
Just repeat it one more time.
MEMBER MILLER: Yes. I would like to
propose that there be a post‑approval study
in people
of color to determine safety and efficacy of this
product in that population.
ACTING CHAIRPERSON CHANG:
Seconded by Dr.
Newburger.
Open to discussion or comment by the
panel?
(No response.)
ACTING CHAIRPERSON CHANG: We
will take a
vote. All
of those in favor of the proposed condition
requesting the sponsor to conduct a post‑approval
study for determining and demonstrating efficacy
and
safety for persons of color, please raise your
hands.
(Whereupon, there was a show of hands.)
ACTING CHAIRPERSON CHANG: Dr.
Olding, Dr.
Doull, Dr. Boykin, Dr. Diegelmann, Dr. Newburger,
Dr.
Miller.
All of those opposed?
(No response.)
ACTING CHAIRPERSON CHANG: All of
those
abstaining, please raise your hands?
(Whereupon, there was a show of hands.)
ACTING CHAIRPERSON CHANG: Dr.
Blumenstein, Dr. Halsey, Dr. LoCicero.
The motion passes.
Dr. Miller, any further recommendation?
(No response.)
ACTING CHAIRPERSON CHANG: Dr.
Newburger?
MEMBER NEWBURGER: I move that
there be a
post‑marketing requirement for a study to
document the
safety of repeated use with this device and that ‑‑
well, I guess that's separate ‑‑ that
the labeling
show that this device is approved on the basis of
data
from one use.
Does that have to be two separate motions?
ACTING CHAIRPERSON CHANG:
No. May I
paraphrase that you were suggesting that the
labeling
suggest that clinical prospective studies have
demonstrated the safety and efficacy for one‑time
use?
MEMBER NEWBURGER: Okay.
ACTING CHAIRPERSON CHANG: With
no mention
of repeated uses?
MEMBER NEWBURGER: If that's how
the FDA
would phrase it.
ACTING CHAIRPERSON CHANG: I
think they
can work with the sponsor with that. The concern is
that the 12‑week data reflects safety
issues regarding
one‑time use. Is that correct?
MEMBER NEWBURGER: And I would
like to
request that there be a post‑approval study
showing