PAXLOVID™ (PF-07321332; ritonavir)

Paxlovid is a novel, COVID-19, oral, antiviral candidate. PAXLOVID™ is a SARS-CoV-2-3CL protease (an enzyme that the coronavirus needs to replicate) inhibitor, which originated in Pfizer’s laboratories. It may have efficacy as a prophylaxis and/or outpatient treatment. Co-administration with a low dose of ritonavir helps slow the metabolism, or breakdown, of PF-07321332 in order for it to remain active in the body for longer periods of time at higher concentrations to help combat the virus.

The Phase 2/3 EPIC-HR (Evaluation of Protease Inhibition for COVID-19 in High-Risk Patients) study began enrollment in July 2021.
The Phase 2/3 EPIC-SR (Evaluation of Protease Inhibition for COVID-19 in Standard-Risk Patients) and EPIC-PEP (Evaluation of Protease Inhibition for COVID-19 in Post-Exposure Prophylaxis) studies, began in August and September 2021 respectively.

Editorial: Safety and efficacy of antivirals against SARS-CoV-2
Crystal structure of SARS-CoV-2 main protease in complex with protease inhibitor PF-07321332
Supervised Molecular Dynamics (SuMD) Insights into the mechanism of action of SARS-CoV-2 main protease inhibitor PF-07321332
Exploring the Binding Mechanism of PF-07321332 SARS-CoV-2 Protease Inhibitor through Molecular Dynamics and Binding Free Energy Simulations
Considerations for the discovery and development of 3-chymotrypsin-like cysteine protease inhibitors targeting SARS-CoV-2 infection
The oral protease inhibitor (PF-07321332) protects Syrian hamsters against infection with SARS-CoV-2 variants of concern
An oral SARS-CoV-2 Mpro inhibitor clinical candidate for the treatment of COVID-19
Computational simulations on the binding and reactivity of a nitrile inhibitor of the SARS-CoV-2 main protease†

Covid-19: UK stockpiles two unapproved antiviral drugs for treatment at home
PFIZER’S NOVEL COVID-19 ORAL ANTIVIRAL TREATMENT CANDIDATE REDUCED RISK OF HOSPITALIZATION OR DEATH BY 89% IN INTERIM ANALYSIS OF PHASE 2/3 EPIC-HR STUDY
SVB Leerink analyst Geoffrey Porges forecasts Paxlovid revenues of $95 million in 2021, $24 billion in 2022, and $33 billion in 2023.
Paxlovid: what we know about Pfizer’s Covid-19 pill.