Statistical Considerations for Clinical Trials During COVID-19: A Two-Stage Adaptive Design for Clinical Trials in Patients with COVID-19 High Risks

Following the PARR strategy, the clinical trial can naturally be constructed as a two-stage adaptive design. The first stage is based on COVID-19 unaffected data from patients who are already enrolled. For clarification, patients enrolled who are affected by COVID-19 would contribute their data as censored observations in the first stage analysis. The second stage includes data from newly enrolled patients following a modified trial design for the remaining trial after post COVID-19.