FDA issues EUA for Merck’s COVID-19 antiviral molnupiravir

The FDA has issued an emergency use authorization for molnupiravir — now the second oral antiviral treatment available for COVID-19.

The drug is authorized for the treatment of mild-to-moderate COVID-19 in adults who test positive for SARS-CoV-2, and who are at high risk for progression to severe disease. It is not authorized for use in patients aged younger than 18 years because it may affect bone and cartilage growth, the agency said.

FDA’s Antimicrobial Drugs Advisory Committee endorsed a recommendation for granting an EUA in a split 13-10 vote on Nov. 30. The recommendation extended to individuals with COVID-19 who are at high risk for serious illness.

“The EUA for molnupiravir is a sign of progress, since it ushers in an era of oral antivirals that can be used by individuals at increased risk of severe disease (elderly and/or immunocompromised patients) when first diagnosed with SARS-CoV-2,” Kenneth H. Mayer, MD, the medical research director of Fenway Health and codirector of the Fenway Institute, told Healio. “This may become similar to how drugs like Tamiflu are used for patients who develop influenza.”

On Wednesday, the FDA granted an EUA for Pfizer’s Paxlovid, an antiviral that was also developed for the treatment of adults who are at risk for severe COVID-19, but it can also be used to treat pediatric patients aged 12 years and older weighing at least 40 kg, or about 88 pounds.

Molnupiravir, which was developed by Merck in collaboration with Ridgeback Biotherapeutics, reduces the risk for hospitalization or death from COVID-19 among high-risk patients, according to phase 3 data. Merck and Ridgeback Biotherapeutics submitted an EUA application on Oct. 11. Since then, Merck has begun manufacturing capsule pills of molnupiravir. The company expects to have 10 million treatment courses produced by the end of the year. With the EUA, the drug may be available to patients within weeks.

“We’re hopeful that we can make a meaningful impact on the pandemic through the development of an effective oral antiviral COVID-19 medicine, pending regulatory discussions,” a Merck spokesperson told Healio.

The drug’s authorization was supported by a phase 3, double-blind, randomized, placebo-controlled trial called MOVe-OUT. The study included patients aged 18 years or older with a chronic medical condition or an increased risk for SARS-CoV-2 infection who had not received a vaccine. Among the 709 participants who received molnupiravir, 6.8% were hospitalized or died during a 1-month period vs. 9.7% of the 699 people who received a placebo. Results of the trial, published in The New England Journal of Medicine, showed that the rate of hospitalization or death through day 29 was approximately 31% lower with molnupiravir than with placebo (HR = 0.69; 95% CI, 0.48 to 1.01).

In comparison, Pfizer’s investigational oral antiviral, Paxlovid, reduced the risk for COVID-19-related hospitalization and death by almost 90% among patients who received the antiviral within days of experiencing symptoms, Healio previously reported.

Of the participants who received molnupiravir, one died during the follow-up period compared with nine people who received placebo. According to the FDA, adverse events included diarrhea, nausea and dizziness.

The drug’s safety and efficacy continue to be evaluated, the agency said.

Reference:

Bernal AJ, et al. N Engl J Med. 2021;doi:10.1056/NEJMoa2116044.