Dr Robert Redfield, Chief of Retroviral Research at the Walter Reed Army Institute of Research, is one of the doctors involved in the clinical trails of a promising new AIDS vaccine rgp160. He believes that HIV infection will be solved within the next decade. At Amsterdam, at the International AIDS conference, the first results from several other rgp160 trails, occurring in the United States, Canada and Sweden, also appeared to be encouraging. In 1987, rpg160 became the first US Food and Drug Administration (FDA) approved vaccine candidate to undergo clinical trials in uninfected volunteers. The study showed that rpg160 was safe. In 1989, Redfield's group at the Walter Reed began the first clinical trials using rgp160 as a therapeutic vaccine on HIV infected volunteers. By the time of the Amsterdam conference in July 1992, 29 out of the 30 original volunteers were responding to the vaccine. There is no sign yet that any of the patients are developing tolerance against the vaccine. rgp160 also appears to stimulate responses against different strains of the HIV virus. And finally the results show the levels of HIV virus in patients are actually declining. Since November 1990, a Phase 2 trail to test the efficacy of rgp160 began. It will shortly have over 600 infected volunteers participating in the trials. The results will be available in 1993 or the year after, which Redfield believes will give the scientific proof that rgp160 vaccination works. Redfield is now more concerned about enough patients being able to have access to rgp160 than he is about its efficacy. In a year, two years at most, he says the Walter Reed Phase 2 trial will have shown whether or not rgp160 does really slow the progression of HIV. If it does, the vaccine will become available for general use. Because of the limited production facilities of MicroGeneSys, where rgp160 was developed, Redfield's guess is that there will be enough rgp160 around to treat 10,000 patients, but there are several hundred thousand HIV positive people in the US alone.