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Paxlovid (Copackaged) (Nirmatrelvir)

Pfizer · FDA-approved approved Small molecule Verified Quality 75/100

Nirmatrelvir inhibits SARS-CoV-2 main protease; ritonavir inhibits CYP3A-mediated metabolism of nirmatrelvir.

PAXLOVID (nirmatrelvir/ritonavir) is indicated for treatment of mild-to-moderate COVID-19 in adults at high risk for severe disease progression. Nirmatrelvir is a potent SARS-CoV-2 main protease inhibitor boosted by ritonavir, a CYP3A inhibitor that increases nirmatrelvir exposure. The combination carries significant drug interaction risk as a strong CYP3A inhibitor, requiring careful medication review and potential dose adjustments. PAXLOVID is not approved for pre-exposure or post-exposure prophylaxis.

At a glance

Generic nameNirmatrelvir
SponsorPfizer
Drug classAntiviral protease inhibitor
TargetSARS-CoV-2 main protease (Mpro, 3CLpro, nsp5 protease)
ModalitySmall molecule
Therapeutic areaInfectious Disease
PhaseFDA-approved
First approval2023

Mechanism of action

Nirmatrelvir is a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antiviral drug that targets the viral main protease. Ritonavir is an HIV-1 protease inhibitor that is not active against SARS-CoV-2 Mpro but serves as a pharmacokinetic booster. Ritonavir inhibits the CYP3A-mediated metabolism of nirmatrelvir, resulting in increased plasma concentrations of nirmatrelvir and enhanced antiviral efficacy.

Approved indications

Common side effects

Drug interactions

Patents

PatentExpiryType

Primary sources

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SourceUsed for
FDA labelMechanism, indications, dosing, boxed warnings, drug interactions
FDA Orange BookPatents + exclusivity

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