A view of the Merck & Co. campus in Linden, New Jersey March 9, 2009. (Photo: REUTERS)

Merck's drug, molnupiravir, developed with Ridgeback Biotherapeutics, was shown to reduce hospitalizations and deaths by around 30% in a clinical trial of high-risk individuals early in the course of the illness.

The US Food and Drug Administration authorized Merck's drug to treat mild-to-moderate COVID-19 in adults who are at risk for severe disease, and for whom alternative COVID-19 treatments are not accessible or clinically appropriate.

Pfizer's drug, Paxlovid, was authorized on Wednesday for people aged 12 and older and has shown to be nearly 90% effective in preventing hospitalizations and deaths in patients at high risk of severe illness, according to trial data.

Both the Merck and Pfizer pills could be promising tools for those who are sick with COVID-19, especially in the face of the fast-spreading Omicron variant.