With an estimated 500,000 cases worldwide, the number of AIDS patients is quickly outpacing the meager advancements made to control the disease and treat those infected with the human immunodeficiency virus. Only one drug, zidovudine (AZT), has been approved by the U.S. Food and Drug Administration to treat HIV infection. Although results from recent clinical trials have found that AZT significantly slows the progression of the disease in patients with early AIDS-related complex (ARC), the drug has been found to cause toxic side effects in many patients with full-blown AIDS symptoms. Furthermore, early signs of drug resistance have some researchers worried that AZT will become obsolete before suitable replacements are available.
Many researchers are now working on potential therapeutic interventions that target different stages in the life cycle of HIV. Perhaps the most advanced in clinical testing are analogs of AZT, which block the enzyme reverse transcriptase and prevent the ...