Review of efficacy trials of HIV-1/AIDS vaccines and regulatory lessons learned: A review from a regulatory perspective

The clinical development of prophylactic HIV-1/AIDS vaccines is confounded by numerous scientific challenges and these in turn result in challenges to regulators reviewing clinical trial applications (CTAs). The search for an HIV-1/AIDS vaccine will only succeed through the conduct of well-designed, well-conducted and well-controlled human efficacy studies. This review summarizes relevant context in which HIV vaccines are being investigated and the six completed efficacy trials of various candidate vaccines and regimens, as well as the lessons learned from them relevant to regulatory evaluation. A companion review focuses on the scientific challenges regulators face and summarizes some current candidates in development. The lessons learned from the completed efficacy trials will enable the development of better designed, potentially more efficient efficacy trials in future. This summary, supported by the World Health Organization (WHO), is unique in that it is meant to aid regulators in understanding the valuable lessons gained from experience in the field to date.