Jitters Jeopardize AIDS Vaccine Trials

Abstract

AIDS vaccine developers have been planning large-scale tests of experimental vaccines in people at high risk of becoming infected with HIV. The National Institutes of Health (NIH) scheduled plans for tests in December 1993. However discouraging findings were reported in November 1993 at the National Institute of Allergy and Infectious Diseases (NIAID) 6th Annual Conference on Advances in AIDS Vaccine Development in Alexandria Virginia relating to neutralizing antibodies which can prevent the virus from infecting cells. In the toughest laboratory test that mixes blood from a vaccinated person with HIV to assess whether vaccines can raise neutralizing antibodies almost all experimental AIDS vaccines failed to trigger a key immune response against HIV. 3 new students were presented at the meeting. The Duke group analyzed blood from 40 people given 6 different vaccines. While most of the samples neutralized lab-adapted strains of HIV not one could neutralize a field isolate. The Walter Reed Army Institute of Research group also failed to find neutralizing activity against primary isolates when they tested 34 of these blood samples. Californias Chiron Corp. had focused on people who had received a vaccine being jointly developed by Chiron and CIBA-GEIGY and selected the 5 vaccines that had the strongest neutralizing antibodies. They then tested these blood samples against primary isolates and could find no activity. However New Yorks United Biomedica Inc. (UBI) demonstrated that blood from one person injected with UBIs vaccine neutralized a field isolate. NIAID announced at the meeting that it will conduct a thorough review of the field isolate issues and decide whether to launch efficacy trials in the United States by the end of 1994. South San Franciscos Genentech said it had more than 200000 doses of HIV vaccine ready because it thought NIAID had made a commitment and the primary isolate question could not nullify other positive animal and human data from experiments with Genentechs vaccine. WHO already is helping Brazil Uganda Rwanda and Thailand prepare for efficacy trials.