Know How COVID-19 Oral Antivirals Compare

You'll start to see the new COVID-19 oral antivirals, nirmatrelvir/ritonavir (Paxlovid) and molnupiravir.

Either is an option for outpatients with COVID-19 who are at high risk of developing serious illness (age 65 or older, diabetes, etc)...regardless of vaccination status.

They're started within 5 days of symptoms...and patients don't currently have to pay for these meds.

If a patient is admitted on nirmatrelvir/ritonavir or molnupiravir, don't be surprised if their own supply is used to complete the course.

Know how these meds compare...and help ensure safe use.

Nirmatrelvir/ritonavir will be used first-line...since it seems more effective.

It's for patients age 12 and over...who weigh at least 40 kg.

Expect most patients to take 3 tablets... 2 nirmatrelvir tabs plus 1 ritonavir tab...bid for 5 days. They come in a blister pack.

Watch for some patients with kidney disease to get a lower dose. They'll take just ONE nirmatrelvir tab bid...but the ritonavir dose won't change.

When this is the case, one AM and PM nirmatrelvir tab should be discarded from all 5 blister cards...and empty blisters covered with manufacturer stickers.

Molnupiravir will be used when other treatments aren't available.

It's for patients age 18 and up...and is 4 caps bid for 5 days.

Keep in mind, molnupiravir should generally be avoided in pregnant patients...since animal studies suggest it may cause birth defects.

And patients with reproductive potential must use reliable contraception during use...and for 4 DAYS afterward in women, and at least 3 MONTHS afterward in men.

Compare the COVID-19 oral antivirals to injectable monoclonal antibodies with our chart, Treatments of Interest for COVID-19.

Key References

  • https://www.fda.gov/media/155050/download (2-3-22)
  • N Engl J Med. 2021 Dec 16. doi: 10.1056/NEJMoa2116044
  • https://www.covid19treatmentguidelines.nih.gov/therapies/statement-on-therapies-for-high-risk-nonhospitalized-patients/ (2-3-22)
  • https://www.covid19treatmentguidelines.nih.gov/therapies/statement-on-patient-prioritization-for-outpatient-therapies/ (2-3-22)
  • https://www.covid19treatmentguidelines.nih.gov/therapies/statement-on-paxlovid-drug-drug-interactions/ (2-3-22)
Hospital Pharmacy Technician's Letter. February 2022, No. 380210



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