Panel to Review GP160 Vaccine Candidate: Report of the Meeting

process by which gpl60 was selected by the Congress for the
proposed efficacy trial. Not only is this a case of law
preempting science and scientific judgment, it is preempting
science in the context of a clinical trial involving human
subjects."
FDA Commissioner David Kessler explained the two roles of
his agency in this review process. "First, FDA
contributes...scientific expertise to the process of assessing
the proper development of therapeutic products...and FDA cannot
abrogate its fundamental responsibilities concerning new
therapies," he said. Second, there is a need to "understand the
broader framework...for this new class of agents," such as gpl60.
This entire class of agents should be properly evaluated before
spending $20 million in federal funds on clinical trials, he
added.
"I hope that, like me, you will wholeheartedly endorse the
spirit, if not the letter of this particular law," Dr. Healy
said. "The challenge is to make sure that the advice that we
transmit to the Congress is not just an academic response...but
[tell Congress] the best action that we should take to advance
the cause of AIDS research and to move quickly on the vaccine
front."
During its first meeting, the "Panel to Review the gpl60
Vaccine Candidate" examined the current status of several AIDS
vaccine candidates including the MicroGeneSys version of gpl60,
discussed a variety of related policy and planning issues, and
considered the challenge of designing and conducting a "simple,"
large-scale multi-vaccine comparative trial as well as the
special issues that would be involved in carrying out a clinical
trial involving HIV-infected infants, children, and pregnant
women. However, the panel did not frame any specific
recommendations.
AIDS THERAPEUTIC VACCINES: REVIEW OF CURRENT STATUS
Several participants at the November 5 meeting joined in
reviewing the range of vaccine candidates now being studied as
products for preventing the transmission of the Human
Immunodeficiency Virus (HIV) or for treating individuals who are
already infected with the virus. Because so many people are
infected with HIV and available treatment regimens are only
partly effective, considerable interest now focuses on developing
vaccine products for this second, or treatment, application.
The rationale behind therapeutic vaccines is that such
products might produce immune responses that would benefit the
patient by slowing or preventing deterioration, explained Dr.
Daniel Hoth, Director of the Division of Acquired
Immunodeficiency Syndrome of the National Institute of Allergy
and Infectious Diseases (NIAID) at NIH. In theory, the
presentation of the correct antigen (or antigens) in an
appropriate vaccine "might induce a response [to HIV] that a
chronic infection does not," added Dr. Fred Valentine from New

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