Pfizer Inc. (NYSE:PFE) has filed a new drug application (NDA) with the FDA for approval of Paxlovid (nirmatrelvir [PF-07321332] tablets and ritonavir tablets) for individuals facing a high-risk for progression to severe illness from COVID-19.
Paxlovid consists of the SARS-CoV-2 main protease inhibitor nirmatrelvir (PF-07321332) and the HIV-1 protease inhibitor and CYP3A inhibitor ritonavir. Because ritonavir blocks the liver enzyme CYP3A related to drug metabolism, its use reduces the effective dose of nirmatrelvir.
The approval, if granted, would cover the use of the antiviral in vaccinated and unvaccinated individuals deemed to have a high risk of progression to severe COVID-19.
The EUA for Paxlovid currently covers the treatment of mild-to-moderate COVID-19 in high-risk individuals at least 12 years old who weigh at least 40 kg. The EUA requires a positive test result and that recipients.
The drug is not authorized for use for more than 5 consecutive days.
Pfizer’s placebo-controlled Phase 2/3 EPIC-HR study (Evaluation of Protease Inhibition for COVID-19 in High-Risk Patients) concluded that Paxlovid led to an 86% reduced relative risk of hospitalization or death from any cause through week 24.
At least half of the U.S. public is believed to have at least one risk factor for severe COVID-19.
Filed Under: clinical trials, Drug Discovery, Infectious Disease