The FDA made molnupiravir the second authorized antiviral pill to treat Covid-19—however, according to the emergency use authorization (EUA), the drug should be near the bottom of the treatment list for patients with SARS-CoV-2.
Merck’s molnupiravir is intended to treat mild-to-moderate Covid-19 in adults who test positive for SARS-CoV-2 infection and who are at high risk for progression to severe Covid-19, including hospitalization and death—a similar indication to Pfizer’s antiviral pill combination, nirmatrelvir plus ritonavir (paxlovid), which was granted an EUA for patients ages 12 and older on Dec. 22. And, also like Pfizer’s drug, molnupiravir is prescription only and should be initiated as soon as possible after diagnosis and within five days of symptom onset.
The difference: molnupiravir is only authorized to be used in situations where patients don’t have any other treatment options.
“Today’s authorization provides an additional treatment option against the Covid-19 virus in the form of a pill that can be taken orally. Molnupiravir is limited to situations where other FDA-authorized treatments for Covid-19 are inaccessible or are not clinically appropriate and will be a useful treatment option for some patients with Covid-19 at high risk of hospitalization or death,” said Patrizia Cavazzoni, MD, director of the FDA’s Center for Drug Evaluation and Research, in a statement. “As new variants of the virus continue to emerge, it is crucial to expand the country’s arsenal of Covid-19 therapies using emergency use authorization, while continuing to generate additional data on their safety and effectiveness.”
The agency explained that, because the drug has the potential to affect bone and cartilage growth, molnupiravir is not authorized for use in patients younger than 18 years. It is also not authorized for use as pre- or post-exposure prophylaxis or for initiation in patients hospitalized with Covid-19. And, importantly, it is not a substitute for vaccination.
The FDA’s authorization for molnupiravir follows almost a month after the agency’s Antimicrobial Drugs Advisory Committee (AMDAC) convened a meeting to discuss the safety and efficacy of the antiviral pill. At that meeting, the drug won an EUA recommendation by the skin of its teeth—AMDAC members were not stunned by the drug’s 30% risk reduction for severe Covid-19, and evidence suggesting the drug had the potential to cause fetal harm in pregnant women and may increase the rate of Covid-19 viral mutations gave the committee pause.
This EUA was based on findings from the randomized, double-blind, placebo-controlled MOVe-OUT trial, which evaluated the safety and efficacy of molnupiravir in non-hospitalized patients with mild or moderate Covid-19 who were at high risk for progressing to severe disease or requiring hospitalization.
“Patients were adults 18 years of age and older with a prespecified chronic medical condition or at increased risk of SARS-CoV-2 infection for other reasons who had not received a Covid-19 vaccine,” the FDA explained. “The main outcome measured in the trial was the percentage of people who were hospitalized or died due to any cause during 29 days of follow-up. Of the 709 people who received molnupiravir, 6.8% were hospitalized or died within this time period compared to 9.7% of the 699 people who received a placebo. Of the people who received molnupiravir one died during the follow-up period compared to nine people who received placebo. Side effects observed in the trial included diarrhea, nausea, and dizziness. The safety and effectiveness of molnupiravir for the treatment of Covid-19 continue to be evaluated.”
The FDA warned that, due to risks of fetal harm, molnupiravir should only be used in pregnant individuals “after the prescribing healthcare provider has determined that the benefits of being treated with molnupiravir would outweigh the risks for that individual patient and after the prescribing health care provider has communicated the known and potential benefits and the potential risks of using molnupiravir during pregnancy to the pregnant individual.”
John McKenna, Associate Editor, BreakingMED™
Cat ID: 190
Topic ID: 79,190,730,933,190,926,192,927,151,725,928,925,934