Molnupiravir in COVID-19: A systematic review of literature

Molnupiravir is a newer oral antiviral drug that has recently been tested in COVID-19. We aim to conduct a systematic review of literature to find out the efficacy and safety of molnupiravir in patients with COVID-19.

We systematically searched the electronic database of PubMed, MedRxiv and Google Scholar from inception until October 15, 2021, using MeSH keywords. Ongoing trials of molnupiravir in COVID-19 were additionally searched from the ClinicalTrials.Gov and ctri.nic.in/Clinicaltrials. We retrieved all the available granular details of phase 1 to 3 studies of molnupiravir in COVID-19. Subsequently we reviewed the results narratively.

Two phase 1 double-blind, randomized, placebo-controlled (DBRPC) studies of molnupiravir showed that 1600 mg daily dose is safe and tolerable, without any serious adverse events up to 5.5 days. One phase 2 DBPRC study found significantly lower time to clearance (RNA negativity) with molnupiravir 800 mg twice daily compared to the placebo (log-rank p value = 0.013) in mild to moderate COVID-19. Interim report of one phase 3 DBRPC study in non-hospitalized COVID-19 found a significant reduction in the risk of hospital admission or death by 50% (p = 0.0012). However, no significant benefit was observed with molnupiravir in the later stage of moderate to severe COVID-19.

Molnupiravir is first oral antiviral drug to demonstrate a significant benefit in reducing hospitalization or death in mild COVID-19 and could be an important weapon in the battle against SARS-CoV-2. However, its role in moderate to severe COVID-19 is questionable and more studies are needed.