Fostering community understanding of sufficient benefit and early stopping for a phase 2B HIV prevention clinical trial in Africa.

Publication Type:

Journal Article


Clinical trials (London, England), Volume 8, Issue 1, p.103-11 (2011)


2011, Africa, Anti-HIV Agents, Center-Authored Paper, Clinical Trials, Phase II as Topic, Early Termination of Clinical Trials, Education, Health Education, Health Knowledge, Attitudes, Practice, Health Promotion, HIV Infections, Humans, National Institutes of Health (U.S.), Residence Characteristics, September 2011, Social Marketing, Therapeutic Equipoise, TIME, United States, Vaccine and Infectious Disease Division


Most trials of interventions are designed to address the traditional null hypothesis of no benefit. VOICE, a phase 2B HIV prevention trial funded by NIH and conducted in Africa, is designed to assess if the intervention will prevent a substantial fraction of infections. Planned interim analysis may provide conclusive evidence against the traditional null hypothesis without establishing substantial benefit. At this interim point, the Data and Safety Monitoring Board would then face the dilemma of knowing the product has some positive effect, but perhaps not as great an effect as the protocol has declared necessary.