News FDA authorizes a second antiviral to treat COVID-19, a Merck pill that can be taken at home: Updates December 23, 2021December 23, 2021Jeanine Santucci and Joel Shannon, USA TODAYComments Off on FDA authorizes a second antiviral to treat COVID-19, a Merck pill that can be taken at home: Updates A day after authorizing the first antiviral pill to treat COVID-19, the FDA on Thursday authorized a second: Merck's molnupiravir. Latest news.