The AZT Story OR Why You Should Never Throw Away Things That Don't Work (At Least Until You Patent Them)
AZT is a failure.
This is because AZT was never intended to fight HIV. It was first developed in 1964 by Jerome Horwitz, a worker at the Michigan Cancer Institute (funded by the National Cancer Institute, which is one of the National Institutes of Health). The goal was to synthesize an anti-tumor agent. AZT failed completely. Horwitz didn't even bother to apply for a patent, so AZT entered the public domain.
Burroughs Wellcome -- later to become Glaxo Wellcome, or whatever it is now -- tested AZT for veterinary purposes, but decided to terminate such testing shortly thereafter. The company maintained a store of the drug, however.
In 1984, the NCI established the Special Task Force on AIDS. Robert Gallo (yes, that Robert Gallo) was the scientific director, and Sam Broder was the clinical director. Their goal was to find drugs that displayed anti-HIV activity. Broder, in particular, began combing through drugs in a one-man pharmaceutical search-and-rescue operation.
When Broder contacted Burroughs Wellcome, it responded with "Compound S" -- AZT, renamed for the purposes of anonymity. In February 1985, Hiroaki Mitsuya of the NCI discovered that, at least in a test tube, AZT blocked the effect of HIV upon helper T-cells by performing as a DNA chain terminator. Duke University confirmed the results. AZT moved into the FDA regulatory process. Although Burroughs Wellcome funded the necessary research, the company refused to test the drug in its own facilities due to its fear of HIV contamination.
The rest is history. AZT became the first drug approved against HIV, and -- after much litigation and other fun government activities -- Burroughs Wellcome received a patent on a drug developed at taxpayer expense, and "rediscovered" by government employees.