Recombinant vesicular stomatitis virus vector vaccines for WHO blueprint priority pathogens

Fathi, Anahita; Dahlke, Christine; Addo, Marylyn M.

The rVSV vaccine platform exhibits many advantages as a vaccine vector backbone for the expression of viral antigens and has been tested as a vaccine candidate against a multitude of emerging infections. As a result of the recent clinical phase I-III trials of VSV-EBOV, we have now gained a significant amount of data in humans, which encouragingly suggest a favorable safety profile of the vaccine candidate as well as swift protection after a single immunization. VSV can readily be attenuated while remaining immunogenic. While the comprehensive details on VSV vaccine-mediated protective immunity have yet to be elucidated, the data generated to date support the premise that protection appears to be primarily inferred by antibody responses. However, cellular immunity is simultaneously induced. In addition, the fact that recombinants can be manufactured quickly with diverse antigens further adds to its value as a vaccine platform for outbreak pathogens. While we have focused here on WHO blueprint priority pathogens, a variety of VSV-based vaccine candidates have been described for other emerging or reemerging pathogens, including enterovirus 71, 126 Chikungunya, 127, 128 West-Nile, 129 Dengue,130 Severe fever with thrombocytopenia syndrome, 131 and Andes viruses. [132] [133] [134] Animal studies of VSV-based vector vaccines against MARV, LASV, NiV, ZIKV, and MERS-and SARS-CoV described above have yielded promising results and the progression of rVSV vaccine candidates to clinical trials may add to the portfolio of effective outbreak vaccines in the foreseeable future.