All Times EDT
Keywords: Seamless development, vaccine, COVID-19
The development of a single pivotal study to demonstrate adequate safety, immunogenicity, and efficacy of a COVID-19 vaccine candidate will be described. This process was characterized by iterative proposals and ongoing consultations with CBER to facilitate rapid evaluation of vaccine candidates and accelerate development. Phase 1 used escalating dose levels in small cohorts in two age groups to identify a preferred candidate and dose level. The selected vaccine regimen was then evaluated seamlessly in Phase 2/3, where safety (reactogenicity and AEs) and immunogenicity (binding and neutralizing antibody responses) were further characterized in the Phase 2 segment. A definitive assessment of efficacy will be based on the very large number of subjects enrolled in Phase 2/3 to accrue the required number of cases. A Bayesian framework was used to incorporate several interim analyses to monitor the trial for efficacy and futility, while controlling the overall type 1 error. Publicly disclosed results will be summarized and discussed, as well as key interactions with regulatory authorities and scientific community.