The Merck COVID pill, officially known as molnupiravir and sold under the brand name Lagevrio, is an oral antiviral medication developed by Merck and Ridgeback Biotherapeutics. It treats mild to moderate COVID-19 in adults at high risk of progressing to severe illness, hospitalization, or death. This medication offers an accessible treatment option for individuals who have recently tested positive for SARS-CoV-2 and are experiencing symptoms.
How the Medication Works
Molnupiravir targets the SARS-CoV-2 virus’s ability to replicate. Once ingested, the medication converts into its active form, β-D-N4-hydroxycytidine (NHC), which mimics the natural building blocks of RNA, specifically cytidine and uridine. The viral enzyme responsible for copying the virus’s genetic material, RNA-dependent RNA polymerase (RdRp), mistakenly incorporates NHC into new viral RNA strands during replication. This incorporation of NHC leads to a process known as “error catastrophe” or “lethal mutagenesis,” where errors accumulate, overwhelming the virus’s proofreading mechanisms. These widespread mutations render the new viral particles non-functional, preventing the virus from multiplying and reducing viral load.
Who Can Take It and How
Who Can Take It
Molnupiravir is authorized for adults 18 and older with mild to moderate COVID-19 and a positive SARS-CoV-2 test result. They must also be at high risk for severe COVID-19 (hospitalization or death) and for whom alternative COVID-19 treatments are not accessible or clinically appropriate. Treatment should begin as soon as possible after a COVID-19 diagnosis and within five days of symptom onset.
How to Take It
The typical dosage is 800 mg, consisting of four 200 mg capsules, taken orally every 12 hours for five days. The capsules can be taken with or without food and should be swallowed whole. Complete the entire five-day course of treatment, even if symptoms improve, to maximize viral clearance. Molnupiravir is not authorized for use in hospitalized patients, nor is it for pre-exposure or post-exposure prophylaxis.
Effectiveness and Safety Profile
Effectiveness
Clinical trials, such as the MOVe-OUT study, investigated molnupiravir’s effectiveness in non-hospitalized COVID-19 patients. This study demonstrated that a five-day course of 800 mg molnupiravir twice daily significantly reduced hospitalization or death compared to a placebo group. Patients also showed a greater reduction in SARS-CoV-2 viral load and improved clinical outcomes.
Safety Profile and Warnings
Common side effects include diarrhea, nausea, and dizziness. While generally well-tolerated, specific warnings exist regarding its use. Molnupiravir is not recommended during pregnancy due to concerns about potential harm to an unborn baby, observed in animal studies. It is not authorized for use in individuals under 18 years of age because it may affect bone and cartilage growth.
Contraception is advised:
Females of childbearing potential are advised to use reliable contraception during treatment and for four days after the last dose.
Males with partners of childbearing potential should use contraception during treatment and for at least three months after the last dose, although the risk beyond this period is currently unknown.
Availability and Current Use
Molnupiravir is a prescription-only medication. Patients can typically obtain this medication through their primary care provider, an urgent care center, or a “Test to Treat” location (which offers examination and antiviral dispensing in one visit). Telehealth options may also be available for obtaining a prescription.
Molnupiravir has transitioned from U.S. government distribution to the commercial market, which may mean patients could encounter out-of-pocket costs. Patient assistance programs are available from the manufacturer, Merck, to help ensure continued access for uninsured or underinsured individuals. Its role in the evolving landscape of COVID-19 treatments often places it among other available antivirals; specific treatment recommendations vary based on individual patient factors, treatment availability, and local guidelines.