Pfizer Inc. Pfizer Inc. and Clear Creek Bio, Inc. today announced a research collaboration and exclusive license agreement to advance the discovery and development of potential inhibitors of the SARS-CoV-2 papain-like protease (PLpro) for the oral treatment of COVID-19. PLpro is an essential enzyme, which, along with the main protease (Mpro), plays an important role in viral replication. This program will expand Pfizer's innovative anti-infective pipeline and, if successful, will complement Pfizer
