In-vitro studies conducted to date show that the clinical candidate PF-07321332 is a potent protease inhibitor with potent anti-viral activity against SARS-CoV-2 This is the first orally administered coronavirus-specific investigational protease inhibitor to be evaluated in clinical studies, and follows Pfizer’s intravenously administered investigational protease inhibitor, which is currently being evaluated in a Phase 1b multi-dose study in hospitalized clinical trial participants with COVID-19 Pfizer Inc. (NYSE: PFE) announced today that it is progressing to multiple ascending doses after completing the dosing of single ascending doses in a Phase 1 study in healthy adults to evaluate the safety and tolerability of an investigational, novel oral antiviral therapeutic for SARS-CoV-2, the virus that causes COVID-19. This Phase 1 trial is being conducted in the United States. The oral antiviral clinical candidate PF-07321332, a SARS-CoV2-3CL protease inhibitor , has demonstrated potent