Zika virus vaccines and monoclonal antibodies: a priority agenda for research and development.

The 2015-16 Zika virus epidemic in the Americas drew global attention to Zika virus infection as a cause of microcephaly and Guillain-Barré syndrome. The epidemic highlighted the urgent need for preventive measures, including vaccines and monoclonal antibodies (mAbs). However, nearly 9 years later, no licensed Zika virus vaccines or mAbs are available, leaving the world's populations unprotected from ongoing disease transmission and future epidemics. The current low Zika virus incidence and unpredictability of future outbreaks complicates prospects for evaluation, licensure, and commercial viability of Zika virus vaccines and mAbs. We conducted an extensive review of Zika virus vaccines and mAbs in development, identifying 16 vaccines in phase 1 or phase 2 trials and three mAbs in phase 1 trials, and convened a 2-day meeting of 130 global Zika virus experts to discuss research priorities to advance their development. This Series paper summarises a priority research agenda to address key knowledge gaps and accelerate the licensure of Zika virus vaccines and mAbs for global use.