On 24 February, VaxGen announced the failure of the first Phase III AIDS-vaccine trial. But, as an article in The New York Times pointed out, many leading AIDS researchers did not expect this gp120-subunit vaccine to be effective, owing to its limited immunogenicity.
The vaccine was designed to target two strains of HIV subtype-B that predominate in North America and western Europe, and the trial, started in 1998, involved 5,100 homosexual or bisexual men and 300 female sex workers.
VaxGen are keen to emphasize the one glimmer of hope emerging from the trial — that rates of infection amongst the black and hispanic participants did seem to be lower than amongst controls. Neil Flynn, a researcher involved in the trial, told Reuters, “there is enough here to warrant a lot more study, particularly in people of African American descent”. Some AIDS-vaccine campaigners took comfort in this news: Peter Piot, Director of UNAIDS said, “the trial provides clear evidence that a vaccine can work” (BBC News). The United States National Institute of Allergy and Infectious Diseases announced plans to investigate why the vaccine was more effective in black and hispanic individuals (reported in The New York Times).
But, others responded more cautiously: “This is at best premature and irresponsible data reporting”, warned Martin Delaney of the AIDS information group Project Inform (Reuters), and The New York Times reported claims made by a prominent biostatistician that proper statistical adjustments had not been made and so the efficacy of the vaccine had possibly been overstated.