re: Merck’s Molnupiravir and Pfizer’s Antiviral Pills - What are the ingredients?

Molnupiravir was in development for flu. It is a nucleoside -based drug, of which several already exist as antivirals. This drug is a prodrug with oral bioavailability. It is a cytidine analog. I have not gotten around to reading all of the literature on this particular drug, but if it works like the others in its class, it will have mixed activity. Ultimately, it will get incorporated into the growing/replicating RNA strand and lead to termination. It will also likely serve to competitively inhibit the polymerase.