Prescribing Information for ▼PAXLOVID (nirmatrelvir / ritonavir) can be found here: Great Britain and Northern Ireland. Adverse event reporting information can be found at the bottom of the page. Please note, there are differences between the SmPC for Northern Ireland and the SmPC for Great Britain. Please refer to the appropriate SmPC depending on where you are based.
Paxlovid has a Conditional Marketing Authorisation in Great Britain. A Conditional Marketing Authorisation means that further evidence on this medicinal product is awaited. New information on this medicinal product will be reviewed when any relevant information of significance becomes available and at least every year and the product information will be updated as necessary.
See PAXLOVID in action
PAXLOVID's active pharmaceutical ingredient is nirmatrelvir, an oral protease inhibitor specifically designed by Pfizer to inhibit the main protease (Mpro), also known as 3-chymotrypsin-like cysteine (3CL) protease enzyme, and to help halt SARS-CoV-2 replication by preventing proteolysis from occurring.1,2
PAXLOVID also contains ritonavir, a CYP3A inhibitor that is widely used as a pharmacokinetic enhancer. Ritonavir is not active against SARS-CoV-2 3CL protease.1,2
1. Proteolysis
In the SARS-CoV-2 life cycle, proteolysis involves the cleavage of viral polyprotein chains by proteases to release the nonstructural proteins that are essential for viral replication.3
2. Mpro
Due to its essential function, Mpro is unlikely to mutate, as any mutations are more likely to create a virus that is unlikely to survive.4
3. Nirmatrelvir
Inhibition of Mpro by nirmatrelvir prevents proteolysis, helping to halt the viral replication cycle.1,2,4
Learn about the oral treatment schedule, dose adjustments and drug interactions.
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*The ABPI Code definition for healthcare professional is members of the medical, dental, pharmacy and nursing professionals and any other persons who in the course of their professional activities may administer, prescribe, purchase, recommend or supply a medicine.
PP-UNP-GBR-7812. January 2024