Oral COVID Drug Slashes Hospitalization and Death Risk, Merck Says

Treatment with the investigational oral antiviral molnupiravir cut the risk of hospitalization and death in half for at-risk COVID-19 patients, manufacturer Merck said on Friday.

An interim analysis of the multinational phase III MOVe-OUT trial found that among 775 higher-risk non-hospitalized COVID-19 patients, 7.3% of those taking molnupiravir were hospitalized or died through day 29 from randomization, as compared to 14.1% of those receiving placebo (P=0.0012).

Moreover, Merck noted there were no deaths in the molnupiravir group versus eight in the placebo group. Based on viral sequencing data from 40% of participants, the drug was effective against the Gamma, Mu, and Delta variants.

Adverse events (AEs) overall and drug-related AEs were comparable in both study arms, the company added.

Given these results, the data monitoring committee recommended stopping the trial, “in consultation with the FDA,” Merck said. The company plans to file for emergency use authorization.

The drug was jointly developed by Merck and Ridgeback Therapeutics, whose CEO Wendy Holman said in the statement that she hoped molnupiravir could make “a profound impact in controlling the pandemic” if authorized for use.

“With the virus continuing to circulate widely, and because therapeutic options currently available are infused and/or require access to a healthcare facility, antiviral treatments that can be taken at home to keep people with COVID-19 out of the hospital are critically needed,” said Holman.

However, Peter Hotez, MD, PhD, of Baylor College of Medicine in Houston, cautioned on Twitter that as with many antivirals, drug resistance could be an issue. “If this is used indiscriminately this can be a problem,” he said.

Hotez also said molnupiravir would likely not be recommended in pregnancy due to concerns about viral mutations, and noted that it was originally developed for the flu. But “unlike hydroxychloroquine or ivermectin this one actually makes sense that it could work” versus COVID-19, he said.

The phase III MOVe-OUT trial was comprised of participants from 170 sites, with more than half in Latin America, 35% in Europe, and 15% in Africa, though the U.S. was included as a participating country.

The interim analysis evaluated data on participants enrolled on or before August 5, 2021, when Merck said they were approaching their planned enrollment of 1,550 participants.

Patients were included if they had symptom onset of laboratory-confirmed mild to moderate COVID-19 within 5 days of randomization, and at least one risk factor for a “poor disease outcome.” Common risk factors included obesity, older age, diabetes, and heart disease.

In the intervention group, 35% experienced an AE versus 40% in the placebo group, while 12% and 11%, respectively, experienced drug-related AEs. More subjects discontinued the drug due to AEs in the placebo group (3.4%) than the molnupiravir group (1.3%), Merck said. The press release did not give details about specific AEs.

Merck said molnupiravir is also being evaluated as post-exposure prophylaxis in the global phase III MOVe-AHEAD study. The company did not announce whether or not they were submitting their data to a peer-reviewed journal for publication.