Paxovir

Nirmatrelvir must be co-administered with Ritonavir. Initiate this treatment as soon as possible after diagnosis of COVID-19 and within 3-5 days of symptom onset. Administer orally with or without food.

Dosage: 300 mg Nirmatrelvir (two 150 mg tablets) with 100 mg Ritonavir (one 100 mg tablet), with all three tablets taken together twice daily for 5 days.

Missed Dose: If the patient misses a dose of this within 8 hours of the time it is usually taken, the patient should take it as soon as possible and resume the normal dosing schedule. If the patient misses a dose by more than 8 hours, the patient should not take the missed dose and instead take the next dose at the regularly scheduled time. The patient should not double the dose to make up for a missed dose.

Adverse events (incidence >1% and subject difference) were dysgeusia, diarrhea, hypertension, and myalgia.

Treatment of an overdose of this tablet should consist of general supportive measures including monitoring of vital signs and observation of the clinical status of the patient. There is no specific antidote for overdose with this tablet.

Indicated for mild-to-moderate COVID-19 positive adult and pediatric patients (12 years of age and older weighing at least 40 kg), who are at high risk for progression to severe COVID-19, including hospitalization or death.

This inhibits the main protease (Mpro) of the SARS-CoV-2. This main protease (Mpro) is also referred as 3C-like protease (3CLpro) or nsp5 protease. This inhibition of Mpro hampers the peptidomimetic activity of SARS-CoV-2. Ritonavir is an HIV-1 protease inhibitor but is not active against SARS-CoV-2 Mpro. Ritonavir inhibits the CYP3A mediated metabolism of Nirmatrelvir, resulting in increased plasma concentrations of Nirmatrelvir

The concomitant use of this tablet and certain other drugs may result in potentially significant drug interactions. Consult the full prescribing information prior to and during treatment for potential drug interactions.

Hepatotoxicity: Hepatic transaminase elevations, clinical hepatitis, and jaundice have occurred in patients receiving Ritonavir.

HIV-1 Drug Resistance: This tablet use may lead to a risk of HIV-1 developing resistance to HIV protease inhibitors in individuals with uncontrolled or undiagnosed HIV-1 infection.