Dr. Mira Behnam of the Institute of Pharmacy and Molecular Biotechnology in Germany has had promising findings that the main protease (Mpro) of SARS-CoV and SARS-CoV-2 can serve as an antiviral drug target. In studying Mpro, which is important for viral replication, Behnam found that this enzyme displays structural heterogeneity, meaning that it contains a variety of binding sites. Traditionally, researchers screen for inhibitors that have the most favorable interaction with the enzyme’s active site and, therefore, can best interfere with viral replication. The implications of Behnam’s research show that some variations of Mpro’s binding site enable the enzyme to bind to residues that can enhance the effect of inhibitors. Knowing then that some conformations of the enzyme may be better for antiviral activity allows for an accelerated development of antiviral drugs against the coronavirus.