Michael Sacco (IMAGE) University of South Florida (USF Health) Caption University of South Florida Health doctoral student Michael Sacco worked with Dr. Chen to determine the interactions between antiviral drug candidate GC-376 and COVID-19's main protease. Sacco is shown here looking at viral protein crystals under a microscope. Credit © University of South Florida Health Usage Restrictions Please use with appropriate caption. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.