This is a phase IIa, double-blind, placebo-controlled, randomized trial, designed to compare the safety, tolerability, and antiviral activity of EIDD-2801 versus placebo as measured by infectious virus detection in symptomatic adult outpatients with COVID-19. The study is a multicenter trial that will be conducted in the United States.

In this study up to approximately 108 participants will be randomized to receive EIDD-2801 or Placebo orally twice a day (BID) for 5 days. The study may enroll up to 5 parts with subsequent doses that may be higher or lower than doses studied in previous cohorts and will be doses that have been studied for safety in a Phase 1 study. Doses will be chosen based on emerging virology and safety data from this and ongoing studies.