Wellcome Details HIV Research Plans

Addressing a symposium at the 10th International Conference on AIDS in Yokohama, Japan, Wellcome's group director for research, development and medical affairs, David Barry, said that despite a number of disappointments, the HIV epidemic was set for a "renaissance of hope." Dr Barry added that it is becoming apparent that the way forward for drug treatment is combination therapy, and that there is good evidence to suggest that, even with the existing types of drug on the market and in development, benefit from treatment will one day be measured in decades rather than years.

Several in vitro studies using combinations of antivirals have been carried out, and Dr Barry presented results of some of these at the meeting. For example, a combination of zidovudine, didanosine (Bristol-Myers Squibb's Videx) and the Hoffmann-La Roche protease inhibitor saquinavir was able to inhibit replication of the virus in the test tube, as was a combination involving zidovudine, didanosine and lamivudine.

Other triple-therapy studies have not produced such striking results, but Dr Barry stressed that so little is known about using the combinations that doses may have been too low and there may be other factors affecting potency. He called for rapid identification of the most-effective and best-tolerated combinations, but conceded that there is only a general relationship between sensitivity in the test tube and efficacy in patients. Furthermore, the ability of the drugs to prevent replication may be limited if the diseases has progressed too far, he suggested, and the risk of additive toxicity may pose a major problem.