The U.S. government will no longer distribute free doses of Merck & Co's COVID-19 antiviral treatment, molnupiravir, starting in November. The decision was announced by the Administration for Strategic Preparedness and Response (ASPR), a division of the U.S. Department of Health and Human Services. The drug, sold under the brand name Lagevrio, will now be sold on the commercial market.
Merck, in collaboration with Ridgeback Biotherapeutics, developed molnupiravir as a potential breakthrough treatment when few options were available. However, it was soon overshadowed by Pfizer's rival treatment, Paxlovid, which showed more impressive data.
The U.S. and EU regulators have recommended against the use of molnupiravir, citing its lower effectiveness compared to Paxlovid. Trial data showed a roughly 30% reduction in hospitalizations and deaths for those at risk of severe disease with molnupiravir, compared to a roughly 90% reduction with Paxlovid.
Furthermore, a study published in the journal Nature last month linked molnupiravir to potentially transmissible mutations in the COVID-19 virus. However, Merck dismissed the study, stating its limitations and expressing confidence in the drug's clinical profile.
Molnupiravir's global sales have significantly declined compared to last year, with Merck expecting sales to be around $1 billion this year. Analysts predict further drops in sales going forward.
Since its authorization, the U.S. government has distributed over 3.2 million courses of molnupiravir, with over 1.4 million doses administered. In comparison, 15.4 million courses of Paxlovid have been delivered, with nearly 10 million used.
Although the distribution of free molnupiravir will cease, the U.S. still has available inventory of Paxlovid, which will continue to be accessible at pharmacies nationwide until it transitions to the commercial market.
To assist individuals who cannot afford the drug, Merck has announced a patient assistance program.
Overall, this change in distribution reflects the diminishing use and effectiveness of molnupiravir compared to Paxlovid, as well as concerns raised regarding potential transmissible mutations.