Adjuvants: tailoring humoral immune responses.

PURPOSE OF REVIEW

The development and availability of new-generation adjuvants beyond aluminum and emulsion formulations, together with a deeper understanding of the mechanistic role of adjuvant formulations in stimulating innate immunity and offer opportunities to improve candidate vaccine designs intended to protect against HIV-1 acquisition.

RECENT FINDINGS

Currently, major efforts in vaccine development focus on improving prime-boost vaccine regimens to enhance efficacy beyond 31% observed in the RV144 phase 3 study and to develop a pathway to induce broadly reactive HIV neutralizing antibodies. Advances in HIV-1 envelope (Env) immunogen design and improved adjuvant formulations are moving at a parallel pace. This review highlights steps underway to rationally pair vaccine concepts with improved adjuvant formulations in preclinical and early phase 1 clinical evaluation.

SUMMARY

New adjuvants with immune-potentiating properties are currently being tested in combination with recent HIV Env-containing immunogens in prime-boost and subunit protein-only regimens. Greater emphasis is being applied to formulation science, delivery, and targeted safety and immune evaluation with these adjuvants in clinical trials. The need to develop an HIV vaccine that induces more potent and long-lived protective immunity will necessitate continued efforts to optimize adjuvanted vaccine formulations.