at all effective in phase I trials, they should be made available to persons who could not enter phase II trials because of ineligibility or geographic barriers. The parallel track, then, would be a large-scale release of an unapproved drug in lieu of the physician-initiated, case-by-case treatment IND request. It was designed to broaden dramatically the availability of experimental drugs at the earliest possible time. New York's ACT-UP, which had become increasingly knowledgeable and sophisticated about drug approval, did the most to popularize this concept.

The first public discussion of the parallel track concept occurred in April 1988 under the leadership of the AIDS Clinical Trials Group. Dr. Anthony Fauci, associate director of the National Institute of Allergy and Infectious Diseases and AIDS coordinator for NIH, ultimately became a defender of the process, which he argued could be accomplished without sacrificing the integrity of concurrent formal clinical trials. Others, including the FDA's then Chief of Antiviral Drug Products, Dr. Ellen Cooper, contended that the 1987 treatment IND regulations were themselves sufficiently flexible to permit very early access and that no new mechanism was needed.

As the parallel track concept became widely discussed in the summer of 1989, enthusiasm was mounting for dideoxyinosine (ddI), a drug similar in composition and mechanism of action to AZT. Dideoxyinosine had shown dramatic in vitro inhibition of HIV replication and, in phase I studies, acceptable toxicity and some evidence of possible efficacy. Phase II trials of the drug were being quickly designed by the sponsor, Bristol-Myers Squibb, and activists pushed for wide access to the drug for those who were ineligible for trials and for concurrent formal trials. Thus, before the parallel track was fully developed as a concept, the White House decided to authorize its implementation, without the usual normal consultation with the scientific community. Because the decision to implement a parallel track circumvented normal procedures, both within the federal government and the larger scientific community, it emerged without the essential component of postmarketing scientific review. Indeed, it is questionable that such a review could be either designed or implemented for the HIV/AIDS patient group due to problems such as compliance with treatment protocols and extensive self-medication. A program was set up by the FDA that, for all intents and purposes, represented a parallel track. Perhaps because it was not officially viewed as such, or because of the great pressure to begin, no evaluation component was included in the program. Moreover, the formal clinical trial of the drug had, in retrospect, especially stringent criteria for entry: a large percentage of people with severe HIV disease were excluded and thus had no alternative for getting ddI other than enrolling in the expanded access program. Finally, initiation of expanded access actually preceded the beginning of the phase II trials, which resulted in a situation in



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