Anti-retroviral therapy in HIV-1-infected persons: concepts and strategies.

HIV has several characteristics that make it difficult to combat; namely its ability to integrate into the host genome, its tendency to mutate, and its ability to infect at least one organ (the brain) with limited regenerative potential. Although these features of HIV make it quite unlikely that a curative therapy for HIV-induced diseases will be found in the near future, it is very encouraging that, in the brief period since HIV was identified as the etiological agent of AIDS, a variety of drugs have been shown to possess anti-retroviral activity. At least one of them (AZT) has already been proven to decrease morbidity and to prolong survival in ARC/AIDS patients. While several single agents with anti-HIV activity in vitro are now being tested for a beneficial clinical effect in HIV-infected patients, it is likely that combination drug therapy will ultimately be more effective in these patients than one drug alone. Such a combination therapy may allow interference with two or even more stages of the HIV life cycle, may lessen the chance of mutation-induced resistance, and may permit additive antiviral activity without additive toxicity of the drugs.