Willingness to participate in HIV-1 vaccine efficacy trials and the effect of media events among gay and bisexual men in New York City: Project ACHIEVE.

Efficacy trials of candidate HIV-1 vaccines require study populations at high risk of infection who adhere to study protocols and who are willing to participate. Data from HIV-1 antibody-negative men (n = 698) enrolled in Project ACHIEVE in New York City were analyzed to assess willingness to participate in efficacy trials, factors influencing willingness, and the effect on willingness of the June 1994 media events about the decision not to proceed with phase III trials and about breakthrough infections during phase I and II vaccine trials. Sixty-eight percent indicated they would definitely or probably be willing to participate. Men enrolled during the time of media events were significantly less willing compared with men enrolled during other periods. These men were also more likely to mention safety of the vaccine, fear or mistrust of research or government, and social risks as important factors in their decision compared with men enrolled during other periods. The most frequently cited motivator for participation was altruism (57%); the most frequently cited barriers were vaccine safety (36%) and vaccine-induced seropositivity (19%). A substantial proportion of this cohort was willing to participate in future vaccine efficacy trials. However, because willingness may be affected by issues of vaccine safety, vaccine-induced seropositivity, and media coverage of these issues, significant efforts are needed for participant and community education, and specific concerns must be addressed in the design and implementation of trials.