
8-10 Because of the potential for significant drug-drug interactions with concomitant medications, this regimen may not be a safe choice for all patients (see below for more information). Ritonavir-boosted nirmatrelvir is expected to be active against the B.1.1.529 (Omicron) variant of concern (VOC), although there is currently a lack of data on the clinical efficacy of ritonavir-boosted nirmatrelvir against this VOC. 4 This efficacy is comparable to the efficacies reported for sotrovimab (i.e., 85% relative reduction) 5 and remdesivir (i.e., 87% relative reduction) 6 and greater than the efficacy reported for molnupiravir (i.e., 30% relative reduction).
#LIST OF CLINICAL TRIALS DONE ON XARELTO RIVAROXABAN TRIAL#
The EPIC-HR trial demonstrated that starting ritonavir-boosted nirmatrelvir treatment in nonhospitalized adults with mild to moderate COVID-19 within 5 days of symptom onset reduced the risk of hospitalization or death through Day 28 by 89% compared to placebo. The Liverpool COVID-19 Drug Interactions website, Table A below, and the EUA fact sheet for ritonavir-boosted nirmatrelvir can be used to identify and manage drug-drug interactions.įor the Panel’s recommendations on the order of preference for outpatient antiviral therapies and the prioritization of outpatient therapies when there are logistical or supply constraints, see Therapeutic Management of Nonhospitalized Adults With COVID-19.Before prescribing ritonavir-boosted nirmatrelvir, clinicians should carefully review the patient’s concomitant medications, including over-the-counter medications, herbal supplements, and recreational drugs, to evaluate potential drug-drug interactions.Ritonavir-boosted nirmatrelvir has significant and complex drug-drug interactions, primarily due to the ritonavir component of the combination.The COVID-19 Treatment Guidelines Panel (the Panel) recommends using nirmatrelvir 300 mg with ritonavir 100 mg (Paxlovid) orally twice daily for 5 days in nonhospitalized patients with mild to moderate COVID-19 aged ≥12 years and weighing ≥40 kg who are at high risk of disease progression 3 treatment should be initiated as soon as possible and within 5 days of symptom onset (AIIa).On December 22, 2021, the Food and Drug Administration issued an Emergency Use Authorization (EUA) for ritonavir-boosted nirmatrelvir for the treatment of patients with mild to moderate COVID-19 aged ≥12 years and weighing ≥40 kg who are within 5 days of symptom onset and at high risk of progressing to severe disease. Coadministration of ritonavir is required to increase nirmatrelvir concentrations to the target therapeutic range.

2 Nirmatrelvir is packaged with ritonavir (as Paxlovid), a strong cytochrome P450 (CYP) 3A4 inhibitor and pharmacokinetic boosting agent that has been used to boost HIV protease inhibitors. 1 It has demonstrated antiviral activity against all coronaviruses that are known to infect humans. Nirmatrelvir is an orally bioavailable protease inhibitor that is active against M PRO, a viral protease that plays an essential role in viral replication by cleaving the 2 viral polyproteins.
