Molnupiravir failed to reduce the risk for hospitalization or death in high-risk COVID-19 outpatients who took the oral antiviral within 5 days of symptoms, a large open-label multicenter trial found.
In more than 25,000 participants in the PANORAMIC study, the rate of all-cause hospitalization or death at 28 days was an identical 0.8% whether individuals were randomized to molnupiravir or usual care (adjusted OR 1.06, 95% bayesian credible interval [BCI] 0.80-1.40), reported Christopher Butler, MD, of the University of Oxford in England, and co-authors.
"Molnupiravir did not reduce already low hospitalizations/deaths among higher-risk, vaccinated adults with COVID-19 in the community," they wrote on the preprint server SSRN.
"Trials of molnupiravir have, thus far, been conducted in largely unvaccinated participants and prior to the emergence of the Omicron SARS-CoV-2 variant," Butler and colleagues noted. "PANORAMIC provides an estimate of the effectiveness of molnupiravir in a multiply-vaccinated population whilst the Omicron SARS-CoV-2 strain is dominant."
The news wasn't all bad for molnupiravir, however.
Time to first reported recovery was a median 9 days in patients taking molnupiravir versus 15 days with usual care (HR 1.36, 95% BCI 1.30-1.40), which met prespecified criteria for success, the researchers said.
And in a group of 73 participants sampled for viral load, SARS-CoV-2 was undetectable at 7 days in 21% of patients in the molnupiravir group compared with only 3% of controls (P=0.039). Mean viral load was also lower in the molnupiravir group at 7 days (P<0.001).