Molnupiravir halved risk of hospitalisation for patients with COVID-19

6th October 2021

Molnupiravir, an investigational anti-viral agent, has been shown to reduce hospitalisation in patients with COVID-19.

According to an interim analysis, Merck and Ridgeback’s investigational anti-viral drug, molnupiravir (MPV), halved the risk of hospitalisation in patients with mild-to-moderate COVID-19. MPV is a pro-drug that is incorporated by RNA polymerase into COVID-19 and which has been shown in preliminary studies, to reduce nasopharyngeal COVID-19 infectious virus and viral RNA.

The results come from the Phase III MOVe-OUT trial, designed to evaluate the safety, tolerability and efficacy of MPV in non-hospitalised patients with COVID-19. Enrolled patients had laboratory-confirmed mild-to-moderate COVID-19 and with an onset of symptoms within 5 days of study randomisation. In addition, all patients were required to have at least one risk factor associated with poor disease outcome. A second trial, examined the value of MPV in hospitalised patients although this was halted after it became apparent that molnupiravir was unlikely to demonstrate a clinical benefit in hospitalised patients.

MOVe-OUT is evaluating molnupiravir at a dose of 800mg twice daily and while the results are yet to be published, the interim analysis seems positive. According a joint press release from the companies, 7.3% (28/385) of patients receiving MPV were either hospitalised or died through to Day 29 following randomisation (28/385), compared with 14.1% (53/377) of placebo-treated (p=0.0012). In addition, after 29 days, there were no deaths were reported in patients who received MPV compared to 8 deaths in the placebo arm.

The incidence of drug-related adverse events was shown to be comparable (12% and 11% MPV vs placebo). Fewer subjects discontinued study therapy due to an adverse event in the molnupiravir group (1.3%) compared to the placebo group (3.4%).

Merck plans to submit an application for Emergency Use Authorisation (EUA) to the FDA as soon as possible and plans to submit marketing applications to other regulatory bodies worldwide.

Source: Merck and Ridgeback press release, October 2021