Large-scale deployment of safe and durably effective vaccines can curtail the COVID-19 pandemic. However, the high vaccine efficacy reported by ongoing phase 3 placebo-controlled clinical trials is based on a median follow-up time of only about two months and thus does not pertain to long-term efficacy. To evaluate the duration of protection while allowing trial participants timely access to efficacious vaccine, investigators can sequentially cross participants over from the placebo arm to the vaccine arm. Here, we show how to estimate potentially time-varying placebo-controlled vaccine efficacy in this type of staggered vaccination of participants. In addition, we compare the performance of blinded and unblinded crossover designs in estimating long-term vaccine efficacy.
Who is this event intended for? Statisticians working on Vaccines or related topics to COVID-19.
What is the benefit of attending? To learn how to evaluate the duration of protection of COVID -19 vaccines and about the performance of blinded and unblinded crossover designs in estimating long-term vaccine efficacy.