Know When to Offer COVID-19 Post-Exposure Prophylaxis

You’ll hear buzz about Regen-COV (casirivimab/imdevimab), the first med to PREVENT COVID-19...especially with cases on the rise.

This injectable monoclonal antibody combo blocks SARS-CoV-2 from entering cells.

It’s already authorized to TREAT mild to moderate COVID-19 in outpatients age 12 or older at high risk of severe illness. This includes patients with diabetes...age 65 or older...or even with a BMI over 25.

Now consider Regen-COV for PROPHYLAXIS in these SAME high-risk patients who are exposed and UNvaccinated...not fully vaccinated...or vaccinated, but not expected to mount an adequate immune response.

“Exposure” is being within 6 ft of a person with COVID-19 for 15 min total. This may change as we learn more about the Delta variant.

Watch for these patients. For example, discuss Regen-COV after an exposure if a patient with diabetes finished their COVID-19 vaccine series less than 14 days ago...or if a vaccinated transplant patient is exposed.

Explain that giving Regen-COV within 96 hours of exposure may prevent COVID-19 in about 1 in 18 UNvaccinated patients at 28 days. It’s currently effective against SARS-CoV-2 variants of concern.

Plus it seems to shorten symptoms by about 2 weeks if patients still get sick.

If patients qualify and want the med, go to the Health and Human Services “Protect Public Data Hub” website to find a site ASAP.

Expect patients to get a single 600 mg/600 mg dose of casirivimab/imdevimab as 4 separate 2.5 mL subcutaneous injections given at the same visit...or an IV infusion over 20 to 50 minutes.

Educate that rare hypersensitivity reactions can occur...so monitoring is needed for at least 1 hour after the dose.

Clarify that the government is currently paying for the med...and many payers will cover the cost of administration.

Reinforce that UNvaccinated patients should still quarantine for 14 days after exposure...and fully vaccinated patients should get tested 3 to 5 days after exposure and follow mask guidance.

Defer COVID-19 vaccination for at least 90 days after Regen-COV...it may interfere with the vaccine immune response.

Get our algorithm, “Mabs” for COVID-19: Patient Assessment and Referral, for eligibility criteria...and managing ongoing exposure.

Key References
  • www.fda.gov/media/145611/download (8-25-21)
  • www.covid19treatmentguidelines.nih.gov/therapies/statement-on-casirivimab-plus-imdevimab-as-pep/ (8-25-21)
  • N Engl J Med Published online Aug 4, 2021; doi:10.1056/NEJMoa2109682
  • www.cdc.gov/coronavirus/2019-ncov/variants/variant-info.html (8-25-21)
Prescriber's Letter. September 2021, No. 370902


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