Early Termination of a Trial of Azidothymidine for the Treatment of Patients with AIDS and AIDS-Related Complex

I. BACKGROUND Researchers first defined the acquired immunodeficiency syndrome (AIDS) as a distinct disease entity in 1981. The disease is characterized by a profound immune deficiency, which results in susceptibility to various opportunistic infections and cancers and has subsequent high mortality. The agent responsible is a human retrovirus, human immunodeficiency virus or HIV, which was discovered in 1984.