The U.S. Food and Drug Administration's top vaccine official, Vinay Prasad, has left the agency after just three months as Director of the Center for Biologics Evaluation and Research, a government spokesperson said. Prasad, an oncologist who was a fierce critic of U.S. COVID-19 vaccine and mask mandates, had been appointed in May by FDA Commissioner Marty Makary. Together they had promised to speed regulatory action and pilot new review pathways. In recent days, criticism of Prasad's tenure has intensified around the agency's handling of a gene therapy for Duchenne muscular dystrophy from Sarepta Therapeutics (SRPT.O), opens new tab. The...