The relatively large number of antiviral agents that have been shown to have activity in the test tube was not anticipated even a few years ago, and their existence has raised new issues regarding priorities in drug testing. At present, simultaneous trials of several agents are ongoing. Whether it is most efficient to test drugs in this manner or whether it would be better to rank drugs and test them in sequence (i.e., starting a new trial only when a previous one has enough subjects) is a matter of ongoing but ill-defined debate. Arguments on the basis of personal choice, which have been predominant in the epidemic (Delaney, 1989a,b), would seem to support the current system of multiple trials. Some have argued that federally sponsored trials might be conducted sequentially, but not the myriad of trials sponsored by pharmaceutical companies and others whose research and development information is proprietary. For a brief time, the AIDS Clinical Trials Group considered requiring that pharmaceutical companies virtually hand over promising drugs they wanted put into the group's trials, but in 1990 the pendulum seemed to swing back to individual companies' dictating many of the details of drug design and monitoring. Thus, it is likely that multiple experimental studies will continue to be conducted concurrently.
Even more interesting is the issue of how resources should be divided between testing candidate antiviral drugs and evaluating drugs used to treat the myriad of complications associated with HIV disease. Critics of the use of resources for the investigation of such supportive therapies have drawn an analogy with the polio epidemic of the 1950s, likening testing of drugs for opportunistic infections to investing large resources in the development of a better iron lung. They argue that the emphasis should be on the underlying cause of AIDS. This viewpoint has been criticized by some clinical investigators, who point out that prophylaxis of PCP has been perhaps more influential in extending survival than the use of AZT. The argument in favor of focusing on causes has also been heavily criticized by activist groups, who interpret the approach as "writing off" the hundreds of thousands of patients with severely impaired immune systems who are perhaps unlikely to benefit from antiviral therapy, however effective it may be, but who still might benefit at least modestly from more effective therapies for opportunistic infections and tumors. Debate on this issue became so intense that congressional hearings were held on the subject, and budgets for opportunistic infection therapies were increased (U.S. Congress, 1991).
Although the debate has often been deemed a political one—between scientists with conflicting research agendas or between future patients and current ones—there remains fundamental scientific uncertainty about the most efficient approach to prolonging the life of AIDS patients. It is likely that interest and resources will continue to shift between the antiviral approach and the supportive (opportunistic infections) approach as new information