Be Ready for Questions About Molnupiravir to Treat COVID-19

You'll hear buzz about molnupiravir, an oral antiviral to treat COVID-19.

Molnupiravir blocks viral replication by incorporating itself into the RNA of SARS-CoV-2...causing viral death.

It's 4 capsules bid for 5 days...and seems well tolerated.

Evidence suggests molnupiravir may prevent hospitalization in about 1 in 35 unvaccinated outpatients age 18 and older with mild to moderate COVID-19...who are at high risk of developing severe illness.

This seems similar to injectable COVID-19 monoclonal antibodies, or "MAbs," (Regen-COV, etc)...but there aren't direct comparisons.

Consider molnupiravir's downsides. For example, there's a concern it may lead to more viral variants...since it incorporates into viral RNA.

Plus animal studies suggest molnupiravir may cause birth defects. It isn't recommended for use during pregnancy or breastfeeding...and has contraception precautions for men or women of reproductive potential.

Don't anticipate that molnupiravir will be added to formulary. It is NOT authorized for patients hospitalized due to COVID-19...since it doesn't seem to shorten recovery time.

Explain that molnupiravir is only for high-risk adult OUTpatients unable to receive another COVID-19 treatment...such as COVID-19 MAbs or the other authorized oral antiviral, nirmatrelvir/ritonavir (Paxlovid).

Point out that patients should start molnupiravir within 5 days of symptoms...versus 10 days with MAbs.

Stay tuned for our review of nirmatrelvir/ritonavir and its place in therapy compared to the COVID-19 MAbs.

See our chart, Treatments of Interest for COVID-19, for more on these oral antivirals, including nirmatrelvir/ritonavir.

Key References

  • N Engl J Med. 2021 Dec 16. doi: 10.1056/NEJMoa2116044
  • https://www.fda.gov/media/155054/download (1-3-22)
  • https://www.covid19treatmentguidelines.nih.gov/therapies/statement-on-therapies-for-high-risk-nonhospitalized-patients/ (1-3-22)
Hospital Pharmacist's Letter. January 2022, No. 380101



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