Food and Drug Administration
Center for
Biologics Evaluation and Research
SUMMARY MINUTES
BLOOD PRODUCTS ADVISORY COMMITTEE
90th
Meeting: August 16, 2007
Committee Members FDA
Participants
Dr. Frederick Siegal, Chair Ms. Jennifer Scharpf, M.P.H.
Dr. Mark Ballow Ms. Lore Fields
Dr. Willarda Edwards Ms. Sheryl Kochman
Dr. George Schreiber
Dr. Irma Szymanski
Dr. Donna Whittaker Guest Speakers
Ms. Judith Baker, M.H.S.A. * Dr. Jerry Holmberg
Dr. Louis Katz ** Ms. Jane Seward, M.B.B.S., M.P.H.
Dr. William Moss
Committee Members Absent Dr. Toby Simon
Dr. Catherine Manno
Dr. Thomas Quinn Non-Voting Temporary Member
Dr. James Allen ***
Temporary Voting Members
Dr. Melvin Berger **** Committee Management Specialist
Dr. Richard Colvin Pearline Muckelvene
* Consumer Representative
Executive Secretary ** Industry Representative
Donald Jehn, M.S. *** Topic I only
**** Topic II only
These summary minutes for the August 16, 2007 Meeting of the Blood Products Advisory Committee were approved on ______September 14, 2007_____
I certify that I participated in the August 16, 2007 Meeting of the Blood Products Advisory Committee and that these minutes accurately reflect what transpired.
// Original Signed // // Original Signed //
_________________________ ___________________________
Donald W. Jehn
Executive Secretary Chair
Food
and Drug Administration
MINUTES
for the
BLOOD PRODUCTS ADVISORY COMMITTEE
90th
Meeting, August 16, 2007
Committee Updates
Dr. Jerry Holmberg presented to the Committee a summary of the May 10-11, 2007 meeting of the DHHS Advisory Committee on Blood Safety and Availability. The next update presented to the committee was by Ms. Jennifer Scharpf on the April 26-27, 2007 FDA workshop on Immune Globulins for Primary Immune Deficiency Diseases: Antibody Specificity, Potency and Testing. Finally, Ms. Lore Fields presented a summary of the August 15, 2007 FDA workshop on Licensure of Apheresis Blood Products.
Informational
Presentations on WHO Biological Standards
Following the updates, the Committee was provided informational presentations on WHO biological standards. Dr. Paul Mied presented a summary of the January 29-30, 2007 WHO Meeting with WHO Collaborating Centres for Biological Standards and Standardization to support the development of WHO biological reference preparations for blood safety-related in vitro diagnostic tests. Dr. Mied outlined the priority projects identified by the WHO Collaborating Centers, including the replacement of existing reference preparations, development of new reference preparations and proposed reference preparations for further discussion. Dr. Mied explained that a five year, In Vitro Diagnostics strategic plan will be presented to the WHO Expert Committee on Biological Standardization (ECBS) for endorsement in October 2007.
Dr. Mei-ying Yu then provided the Committee an overview of potency and safety standards for plasma derivatives. Dr. Yu summarized CBER’s role in developing and establishing global potency standards for plasma derivatives through close collaboration with the WHO Collaborating Centers. She then reviewed potency standards for clotting factors, immune globulins and albumin, as well as safety standards for in-process control methods for testing for Parvovirus B19 and Hepatitis A in plasma for further manufacturing. Finally, Dr. Yu reviewed standards currently under development.
Next, Ms. Sheryl Kochman reviewed the joint WHO/FDA minimum potency standards for blood grouping reagents. She discussed the importance of new standards development to ensure relevance to current blood grouping regents derived from monoclonal antibodies, as well as adequate supplies. Ms. Kochman summarized the collaborative process for the development of three new international standards: anti-D standard 99/836, anti-A standard 03/188 and anti-B standards 03/164. She stated that all three standards are now available through CBER.
Topic I:
Response
to the Office of Blood Research and Review Office Level Site Visit for
Research, July 22, 2005
Dr. Kathryn Carbone provided an introduction to the Committee on research programs conducted at the Center for Biologics Evaluation and Research (CBER). Dr. Carbone summarized CBER’s research management initiative and identified CBER’s 2007 research priorities. She also explained CBER’s research evaluation program for investigators, comprised of annual internal reviews and four year cycle reviews by both external and internal committees. Finally, Dr. Carbone outlined the process for Office level review of research programs and summarized the findings of the Advisory Committees in response to the 2005-2006 Office level site visits.
Dr. CD Atreya then provided the Office of Blood Research and Review (OBRR) response to the July 22, 2005 site visit. Dr. Atreya discussed the four key issues identified by the BPAC in their report: 1) sufficient time and qualified personnel to perform mission related research; 2) support for mission critical research; 3) research prioritization and; 4) visibility of OBRR research. He then explained how OBRR has addressed each of the issues. Dr. Atreya summarized the key scientific needs identified by OBRR and the process for determining the Office’s six priority research areas. He stressed that major program changes have been implemented to ensure a more structured and transparent managed research program within the OBRR.
No public comments were presented during the Open Public Hearing.
During the discussion period, the Committee responded favorably to the OBRR’s response to their report. The Chair of the Site Visit Committee thanked the OBRR staff for their thoughtful response to the report and said he was also pleased to see a response by CBER management. The Chair said he was encouraged by the progress and noted a clear improvement in the quality and focus of OBRR’s research since 1998 when the first report was published. In agreement with other Committee members, the Chair expressed concern over appropriate resources to sustain the research programs. Further, the members commented on the increased use of the CBER website to showcase CBER research. Members also asked for clarification on how dedicated time for research is evaluated and protected. One member asked if OBRR has experienced any change in recruitment or retention of investigators since the 2005 site visit. Members also questioned how the FDA consolidation at White Oak may affect dedicated laboratory space and collaborative efforts with the National Institutes of Health. Finally, Committee members commented on the development of reference standards as part of the managed research program and asked specific questions related to OBRR’s efforts on biovigilence and clinical guidelines for transfusion medicine.
Topic II: Measles
Antibody Levels in
In the afternoon, Dr. Basil Golding introduced the topic of measles antibody levels in U.S. Immune Globulin products. He presented the issue that measles antibody levels are dropping in Immune Globulins to the point that products may fail lot release specification tests and this may lead to product shortages. Dr. Jane Seward from the Centers for Disease Control and Prevention provided an overview of current measles epidemiology in the United States and indicated that most cases are imported and outbreaks are small (66 cases since 2001). Following Dr. Sewards’s presentation, Dr. William Moss from Johns Hopkins Bloomberg School of Public Health discussed measles in immunocompetent and immunodeficient hosts, indicating that antibodies and T cell play important roles in host defense. Dr. Toby Simon then presented CSL Behring’s data on measles antibody titers in plasma donors showing that titers were decreasing mainly because the proportion of older donors with higher titers and that were naturally infected are decreasing. Dr. Don Baker, representing Baxter Healthcare Corporation, presented data from a longitudinal study of measles antibody titers in IGIV and Dr. Othmar Zenker, representing CSL Behring, presented data on measles antibody titers in primary immune deficient patients receiving Immune Globulin products. According to Dr. Zenker’s data the lot release specification could be decreased to 0.30 x CBER standard and still result in protective trough levels.
During the Open Public Hearing, Ms. Mary Gustafson presented the Plasma Protein Therapeutics Association statement of measles antibody levels in US Immune Globulins and supported CBER’s proposal to lower the minimum specification for lot release. Ms. Marcia Boyle, president of the Immune Deficiency Foundation, then commented on FDA’s proposal to lower the minimum titer for measles antibodies in US Immune Globulins and expressed her concern that FDA should act to ensure product is available.
The following issues were discussed before the Committee formally addressed the questions posed by FDA:
o Committee members expressed concern that if anti-measles titers continue to decline, FDA will be facing this same issue in the near future. The Committee stressed the importance of collecting data now to determine the minimum protective level. One Committee member asked if measles titer is needed as a measure of potency at all.
o
One Committee member who supported lowering the
measles antibody specification level indicated the issue would not need to be
reexamined unless: 1) antibody levels in immune globulins are demonstrated to
decline further; 2) measles occurs in patients with primary immune deficiency
diseases (PIDD), or 3) epidemiological data show measles resurgence in the
o The Committee discussed the precautions taken currently for PIDD patients who travel to measles endemic areas.
The Committee then addressed the following questions:
1. Do Committee members concur with the FDA proposal to lower the minimum measles antibody specification for IGIV and IGSC from 0.60 x CBER standard, to 0.48 x CBER standard?
The committee concurred with the FDA proposal (13 yes votes, 1 no vote). No further comments were discussed by the committee.
2. CBER
is considering requesting additional studies to confirm that PIDD patients will
achieve trough levels of measles antibodies above 120 mIU/mL if treated with IGIV and IGSC products that meet the
proposed revised potency standard of 0.48 x CBER standard. Do the Committee members agree that this
information is needed?
The committee agreed that additional studies are needed (13 yes votes, 1 no vote).
The Committee discussed that additional studies are needed to ensure patients are achieving protective trough levels. One member commented that while 120 mIU/mL correlates with protection, it does not define immunity. It was also discussed that patients with T-cell deficiencies are at the greatest risk and should be treated with higher doses to achieve titers that achieve "sterilizing immunity."
3.
Please comment on the need for and feasibility of any alternative
strategies that CBER should consider to reduce the likelihood of failed lots of
IGIV and IGSC based on potency testing for measles antibodies in order to
ensure availability of product for PIDD patients.
The Committee discussed the variability of measles titers and titers for other pathogens (e.g. S. pneumoniae, H. influenza and varicella zoster) in immune globulin products. The Committee agreed that it would be helpful for clinicians concerned about a particular pathogen if information about antibody titer levels was included on the product label. One Committee member cautioned, however, that while information on the label may lead to the use of a particular product, it does not always predict clinical outcome.
One Committee member asked if Hepatitis A
antibodies are also declining in IGIM, which is indicated for post-exposure
prophylaxis to Hepatitis A. FDA
responded that anti-HAV titers have declined and noted that titers in recovered
plasma are lower than Source Plasma.
Finally, the Committee commented that physician and patient education may be needed so that adjustments in therapy can be made to assure that protective titers are achieved for PIDD patients going on travel or in times of measles outbreak.