Oral COVID-19 antiviral, Paxlovid is approved by MHRA (UK).

PF-07321332/ritonavir is a novel protease inhibitor that includes PF-07321332, a drug designed to block the activity of the 3C-like (3CL) protease, also known as the main protease (Mpro) inhibitor, that was specifically designed in Pfizer’s laboratories to combat SARS-CoV-2. 3CL protease is a virally encoded protein that is essential to enable the virus to replicate; by inhibiting this viral protein, PF-07321332 reduces the ability of the virus to reproduce. PF-07321332 is co-administered with a low dose of ritonavir to help slow the metabolism, or breakdown, of PF-07321332 so that it remains active in the body for longer periods of time at higher concentrations to help combat the virus. Under this authorisation, PF-07321332/ritonavir can be prescribed as an at-home treatment, potentially helping patients avoid severe illness.

The MHRA based its decision on positive results from the Phase II/III EPIC-HR (Evaluation of Protease Inhibition for COVID-19 in High-Risk Patients) interim analysis, which enrolled 1,219 non-hospitalised adults with confirmed COVID-19 who were at increased risk of progressing to severe illness.2 607 patients received PF-07321332/ritonavir and 612 patients received placebo.