No acquisition: A new ambition for HIV vaccine development?

Development of a safe and effective prophylactic HIV-1 vaccine presents unique challenges. The pessimism following the failure of two HIV-1 vaccine concepts in clinical trials, HIV-1 gp120 and an adenovirus-based approach to induce only cellular immune responses, has been replaced by cautious optimism engendered by the RV144 trial outcome, the isolation of several new broadly reactive neutralizing monoclonal antibodies, and recent primate model data indicating prevention of viral acquisition by active or passive immunization. Intense efforts are underway to optimize immunogen design, adjuvants, and the tools for preclinical evaluation of candidate vaccines in primates, where correlates of protection can be examined in detail — as proof-of-concept for clinical trials.

► RV144 trial data and recent non-human primate studies suggest that HIV-1 acquisition may be preventable by vaccination. ► Induction of virus-specific humoral as well as cellular immune responses is an important goal for AIDS vaccine development. ► Recently, several new tools have been developed to determine preclinical efficacy of candidate HIV-1 vaccines in non-human primates.