A U.S. Patent for “Methods and Compositions for Inactivating Enveloped Viruses” was awarded to Biogen on July 7th, 2020. Aspects of the present invention provide therapeutic recombinant protein preparations and methods of preparing therapeutic recombinant protein, which methods include contacting recombinant protein preparations with zwitterionic detergent at or above critical micelle concentration of the detergent. Learn More