Far and away the area of greatest interest and accomplishment in infectious diseases over the past year is the acquired immunodeficiency syndrome (AIDS). Important advances have occurred in virology, immunology, and epidemiology, and, for the first time, there is a glimmer of hope in treatment and prevention.
Approval of zidovudine (Retrovir, azidothymidine [AZT]) by the Food and Drug Administration slightly more than one year after the first patients were entered into a clinical trial is a remarkable achievement. Zidovudine is an analogue of thymidine. It enters cells, is phosphorylated by cellular kinases, competitively inhibits human immunodeficiency virus (HIV) reverse transcriptase, and terminates DNA chain formation. It is selective for viral reverse transcriptase and has little effect on host cell enzymes. Concentrations of 0.13 μg/mL or less can inhibit HIV replication. It is also active against the more classic retroviruses of some animals and against other lentiviruses, the family to which