There was a lot of hoopla about a new oral anti viral drug for Covid 19 last week. I like to wait for independent analyses like that provided by the nonprofit, The Medical Letter. To date there are only three proven treatments for mild to moderate Covid 19 in outpatients. All of these are monoclonal antibodies that require an intravenous infusion.
- Bamlanivimab plus etesevimab; or
- Casirivimab plus imdevimab; or
- Sotrovimab 500 mg intravenous (IV) infusion
This drug, Molnupirivir, is an oral medication. While their were enthusiasts for hydroxychloroquine and it’s successor, Ivermectin, there was never any proof that these worked. Unfortunately, that hasn’t prevented them from being prescribed. This drug could be used much like Tamiflu is used for Influenza. Here is the report from The Medical Letter.
Merck and Ridgeback Biotherapeutics have announced that they will submit an application to the FDA for Emergency Use Authorization (EUA) for their investigational oral antiviral drug molnupiravir for treatment of COVID-19.1 If the EUA is granted, molnupiravir would be the first oral antiviral drug to be authorized in the US for treatment of COVID-19. The IV antiviral drug remdesivir (Veklury) was approved by the FDA for treatment of COVID-19 in hospitalized patients in October 2020.2
MECHANISM OF ACTION — Molnupiravir is a prodrug of the synthetic nucleoside derivative β-D-N4-hydroxycytidine. It targets viral RNA polymerase, resulting in the introduction of copying errors during viral RNA replication.3
CLINICAL STUDY — The efficacy of molnupiravir is currently being investigated in a randomized, double-blind, placebo-controlled phase 3 trial (MOVe-OUT) in non-hospitalized adult patients with mild to moderate COVID-19. Eligible patients had laboratory-confirmed SARS-CoV-2 infection with symptom onset within 5 days of randomization and at least one risk factor associated with poor disease outcome (e.g., obesity, age ≥60 years, diabetes, or heart disease). According to the results of a planned interim analysis released by the manufacturers, among 775 patients who were initially enrolled in the trial, molnupiravir reduced the risk of hospitalization or death through day 29 by approximately 50% (7.3% vs 14.1% with placebo). There were no deaths in the molnupiravir group compared to 8 deaths in the placebo group. The efficacy of the drug appears to be similar among the Gamma, Delta, and Mu variants. Based on these interim results, enrollment in MOVe-OUT has been stopped.1
ADVERSE EFFECTS — According to the manufacturers, adverse effects in MOVe-OUT were similar with molnupiravir and placebo. Fewer patients discontinued molnupiravir due to an adverse event (1.3% vs 3.4% with placebo).1
DOSAGE — The dosage of molnupiravir in the clinical trial was 800 mg twice daily for 5 days.4
CONCLUSION — The manufacturers of the investigational oral antiviral drug molnupiravir plan to file an application for Emergency Use Authorization (EUA) for the drug based on unpublished interim results of a randomized, placebo-controlled clinical trial which showed molnupiravir significantly reduced the risk of hospitalization or death in outpatients with mild to moderate COVID-19.
- Merck. Merck and Ridgeback’s investigational oral antiviral molnupiravir reduced the risk of hospitalization or death by approximately 50 percent compared to placebo for patients with mild or moderate COVID-19 in positive interim analysis of phase 3 study. October 1, 2021. Available at: https://bit.ly/3l0Q0Y9. Accessed October 4, 2021.
- Remdesivir (Veklury) for COVID-19. Med Lett Drugs Ther 2020; 62:186.
- F Kabinger et al. Mechanism of molnupiravir-induced SARSCoV-2 mutagenesis. Nat Struc Mol Bio 2021; 28:740.
- NIH. Efficacy and safety of molnupiravir (MK-4482) in non-hospitalized adult patients with COVID-19 (MK-4482-002). Available at: https://bit.ly/3Dbo7CZ. Accessed October 4, 2021.
