Researchers find Ritomavir boosted Nirmatrelvir outperforms Molnupiravir in early COVID 19 treatment

In an ongoing international study published in The Lancet Infectious Diseases , researchers have found that both molnupiravir and ritonavir-boosted nirmatrelvir accelerate SARS-CoV-2 viral clearance in COVID-19 patients, with ritonavir-boosted nirmatrelvir demonstrating significantly greater antiviral efficacy.

The PLATCOV trial, conducted in Thailand, involved low-risk adult patients aged 18-50 with early symptomatic COVID-19, defined as having symptoms for less than four days. Participants were randomly assigned to one of seven treatment groups, including molnupiravir, ritonavir-boosted nirmatrelvir, and a control group with no study drug.

Among the findings:

Ritonavir-boosted nirmatrelvir demonstrated a remarkable 84% faster viral clearance compared to the control group, while molnupiravir showed a 37% improvement.

In a non-inferiority comparison between molnupiravir and ritonavir-boosted nirmatrelvir, the latter proved superior, with 25% faster viral clearance.

Viral rebound occurred more frequently following nirmatrelvir treatment than in the control or molnupiravir groups.

Molnupiravir was removed from the study platform after reaching a predefined inferiority margin compared to ritonavir-boosted nirmatrelvir.

All reported treatment groups showed no adverse events of grade 3 or worse, or serious adverse events.

Reference: Antiviral efficacy of molnupiravir versus ritonavir-boosted nirmatrelvir in patients with early symptomatic COVID-19 (PLATCOV): an open-label, phase 2, randomised, controlled, adaptive trial, William H K Schilling et al.Published:September 28, 2023

DOI: https://doi.org/10.1016/S1473-3099(23)00493-0