DR. JACOBS: Thank you, Dr. Brown, and welcome to members of the Committee.
Today we are again bringing the question of deferral from blood donation of persons with possible foodborne exposure to bovine spongiform encephalopathy, BSE, as a precautionary measure to reduce the risk of blood transmission of new variant Creutzfeldt Jakob disease. And we are asking the Committee at this time, as we did in December, to consider this in the light of possible shortages.
Next, the current status. So far there have been no cases of either BSE or new variant CJD reported in the U.S. We're aware and we discussed in December the precautionary measures which have been taken in the U.K. First, they are not using U.K.-sourced plasma; and, secondly, they are implementing universal leukoreduction.
We took the question to our advisory committee in December. And that entire transcript is available on our Web site. I want to mention that in December and again today, in order to have continuity with the Blood Products Advisory Committee, which is also a scientific advisory committee to us, we have invited Dr. Hollinger, who is chair of that committee; Dr. Leitman; and Dr. Nelson.
In order to have continuity with the BSE Committee, which is advisory on the PHS level to Dr. Satcher, we have invited as a guest Dr. Gilcher. We also have guests: Dr. Katz and Dr. Sayers from the blood banking community, and we have also included Drs. Hueston, Schonberger, and Tramont, who served in December as temporary voting members.
Next. In December, we asked the Committee to vote on two votes. I'm going to go through what those votes were. The first one is: Should FDA recommend new deferral criteria for blood donors to attempt to reduce a theoretical risk for transmitting new variant Creutzfeldt Jakob disease be excluding donors potentially exposed to the agent of bovine spongiform encephalopathy? The Committee voted nine yes and six no.
Next overhead. Should FDA recommend excluding donors who have resided in the United Kingdom or other BSE countries? The Committee voted 15 yes, unanimous, to remove "or other BSE countries."
Dr. Williams, who will also speak today, presented data from the REDS donor survey which showed that 11 percent of the current donor base in the United States was in the U.K. between 1984 and 1990. And, thus, the Committee voted 12 in favor of a survey of blood donors addressing residence or travel in the U.K., including the duration and time period.
These survey results will also be used for the questions: Should FDA recommend distinguishing between donors who were resident in BSE countries during periods of higher versus lower risk of exposure to the BSE agent? And should FDA recommend exclusion of donors who had less intense exposure to beef products based on limited travel to a BSE country? Those questions will all be revisited today.
I want to just put on the record and mention the other votes which were taken in December. Should FDA recommend withdrawal for blood components based on these donor deferral criteria? The vote was seven yes, five no.
And should FDA recommend withdrawal for plasma derivatives based on these donor deferral criteria? Voted eleven no, one yes.
Next one, please. In addition to these questions on deferral of donors, in December we also asked the Committee to consider the actions that FDA would take if there were a report of a possible case of new variant CJD.
We're going to refer those to CDC, but considering our precautionary withdrawal policy for new variant CJD, we asked: Should FDA recommend precautionary quarantine or withdrawal for plasma derivatives to which a possible new variant CJD donor contributed pending confirmation of the clinical diagnosis?
The Committee voted eight yes, one no, one abstained, but they asked us to revisit this question of our operational definition of a possible new variant CJD case. And in the second part of today's deliberations, after the vote on deferral, we will go back to that question.
The Committee also voted that a tonsil biopsy negative for protease-resistant prion would not be sufficient to make product withdrawals unnecessary.
Next overhead, please. For today's agenda, we have scheduled talks by Dr. Alan Williams on the survey of U.S. blood donors; secondly, on the demographics of BSE and what it can tell us about new variant CJD by Dr., that should be, Christl Donnelly, who is head of the Statistical Unit at the Welcome Trust at University of Oxford in England.
You may remember in December we mentioned that the Department of Health in England had commissioned a risk assessment. That is now publicly available. It was peer-reviewed. It was done by Det Norsk Veritas. Philip Comer, who was in charge of that risk assessment, will discuss it.
We, unfortunately, omitted on this one of our colleagues who is speaking. That is Dr. Nightingale. He is the Executive Secretary of the Committee on Blood Safety and Availability. That's the committee I mentioned that reports to Dr. Satcher. And he will talk about the reserve capacity of the U.S. blood supply.
And, finally, because Canada is going through a similar process, we asked Dr. Penny Chan, who is the Executive Secretary of the Canadian National Blood Safety Council, to tell us about their recent open forum.
In addition, we have available for comparative purposes results of the two Canadian travel surveys that were done. And Dr. Marc Germain can answer any questions during the open hearing part or the Committee discussion part.
Finally, I want to mention on the agenda that we are having a second part to today's discussion. Dr. Dorothy Scott will talk about the operational definition of possible new variant CJD for use in making decisions about quarantining blood or blood products.
Now, what are the questions that we are taking to the Committee today? In light of the additional information brought forward since the December 18th, 1998 meeting of the Committee, next overhead, should FDA recommend new deferral criteria for whole blood donors to attempt to reduce the theoretical risk of transmitting new variant CJD from transfusions based on foodborne exposure to BSE in the U.K., 1B) If so, what deferral criteria should FDA recommend, including time period, nature, and length of exposure?
And a second question -- I want to note that for the questions today, we have separated out the questions for whole blood donors, which were addressed in Question 1.
Question 2 has the same approach to plasma donors. Should FDA recommend new deferral criteria for donors of source plasma and recovered plasma for fractionation to attempt to reduce the theoretical risk of transmitting new variant CJD from plasma derivatives based on foodborne exposure to BSE in the U.K.? And 2B) If so, what deferral criteria should FDA recommend?
Now, in addition to giving these formal questions to the Committee, on which we ask them to vote, we also give them an issues summary. That includes some questions, and I want to just read those into the record.
For the decisional issues directly related to the vote, based on the survey results and scientific knowledge, will additional donor deferral criteria reduce the possible risk of new variant CJD? Secondly, what would be the estimated impact on the supply of blood and blood products in the U.S. of additional donor criteria? And, third, should the donor deferral criteria be the same for whole blood and for source or recovered plasma?
Then we listed also related issues. Can the time course of the BSE epidemic be described? Is the impact of the feeding ban and other restrictions known? Can the time course of the BSE epidemic be related to the risk of foodborne exposure to the BSE agent?
Is the risk of foodborne exposure well-characterized? Can the risk be quantified with factors such as amount, length of time, or type of food consumed? Is dietary history, for example, eating meat, useful to identify individuals at increased risk?
Can the risk of developing new variant CJD be related to the time course of the BSE epidemic? Can individuals at risk for new variant CJD be identified? Is there a genetic or physical predisposition? And, finally, can the potential risk of transmission of new variant CJD be a blood product, be estimated upon currently available data?
And, last, I'd like to mention what our plans are for follow-up. First, today is the day at which the survey results are being presented for a vote for the Committee. Next, these recommendations are considered within FDA. We consult with other PHS agencies, which include NIH and CDC and the Department.
There is a possibility of discussing recommendations at the next PHS Advisory Committee on Blood Safety and Availability; and then, finally, announcement of a revised guidance, which would include the recommendations.
CHAIRMAN BROWN: Thank you very much, Dr. Jacobs.
It may have struck members of the audience, as it has me from time to time, that the issue of blood safety and CJD is grist for the mill of three different committees: this one, Blood Product Advisory Committee; and the Blood Safety and Availability Committee.
And, for the record, I think it would be very nice if -- in view of the fact that the FDA has quite justifiably invited one or more members of the other committees to our meetings for the same continuity -- it would be very nice if one or more members of this Committee occasionally were invited to the other committees.
It's somewhat disappointing to render decisions or advice from the Chair and this Committee only to have it totally reversed within two months on the basis of recommendations by other committees.
So, having got that off my chest, we'll continue now with a detailed presentation by Dr. Williams.