Pfizer said Friday that its easy-to-administer Covid-19 pill, used in combination with a widely used HIV drug, cut the risk of hospitalization or death by 89% in high-risk adults who’ve been exposed to the virus.

It’s now the second antiviral pill behind Merck’s to demonstrate strong effectiveness for treating Covid at the first sign of illness. If cleared by regulators, it would likely be a game-changer in the ongoing global pandemic fight. Pfizer said it plans to submit its data to the Food and Drug Administration “as soon as possible.”

Pfizer’s pill, scientifically known as PF-07321332, is part of a class of medicines called protease inhibitors and works by inhibiting an enzyme the virus needs to replicate in human cells. Protease inhibitors are used to treat other viral pathogens such as HIV and hepatitis C.

The HIV drug helps slow the metabolism, or breakdown, of Pfizer’s pill in order for it to remain active in the body for longer periods of time at higher concentrations, the company said.

The company said its data on the drug is based on a mid-to-late stage study of 1,219 adults who had at least one underlying medical condition and a laboratory-confirmed infection within a five-day period. Participants were also given a low dose of ritonavir, a medication commonly used in combination treatments for HIV.

source cnbc.com