Overview of antiretroviral therapy.

All of the agents that are available for the treatment of human immunodeficiency viral infection belong to the class of drugs called nucleoside analogs that act on the virus's reverse transcriptase enzyme. As their use expanded for increasing cohorts of patients and stages of disease, it became clear that additional agents were required that would act at different points in the virus's life cycle. Several different classes of drugs have been identified and evaluated in the laboratory and the clinic. At this point, one of the most promising that is undergoing clinical trials is the proteinase inhibitors. It is important to assess the data for currently available drugs and use that information to determine the most appropriate role for proteinase inhibitors. To appreciate their potential role best, we must also glance over the horizon at other experimental treatments.