Rising cases will renew focus on COVID-19 monoclonal antibodies (casirivimab/imdevimab, etc) for treating mild to moderate illness.
Patients. Early data now suggest casirivimab/imdevimab (Regen-COV) reduces mortality in patients HOSPITALIZED due to COVID-19.
But it's not authorized for these patients yet...and the dose showing benefit is over 6 times the current authorized dose.
For now, continue to focus "mab" use on OUTPATIENTS positive for COVID-19 who are 12 years and up...with mild to moderate symptoms for less than 10 days...and at high risk of severe COVID-19 (diabetes, etc).
Products. Rely on casirivimab/imdevimab for now.
Expect limited use of sotrovimab, the most recently authorized mab.
Outcomes with sotrovimab seem similar to other mabs. But sotrovimab costs about $2,100/dose...and so far, the government hasn't purchased it to provide "at no cost" like other mabs for COVID-19.
And keep in mind, bamlanivimab/etesevimab distribution is currently paused...due to reduced Beta and Gamma viral variant susceptibility.
Clarify that casirivimab/imdevimab or sotrovimab seems to retain activity against these variants.
Administration. Ensure your protocols are updated to reflect the latest casirivimab/imdevimab dosing and administration.
Reduce the dose from 1,200 mg/1,200 mg to 600 mg/600 mg. Data show similar efficacy with the lower dose.
And be aware, it can now be given subcutaneously instead of just IV...the other COVID-19 mabs are IV-only.
But save subcutaneous use of casirivimab/imdevimab for cases where IV isn't feasible or would delay treatment.
Authorization for the subcutaneous route is based on a comparable reduction in viral load...not outcomes data. Plus giving it subcutaneously requires 4 injections of 2.5 mL each.
Use our algorithm, "Mabs" for COVID-19, for quick reference. It's updated with details about using casirivimab/imdevimab for post-exposure prophylaxis...its latest authorized use.
See our chart, Treatments of Interest for COVID-19, for more guidance about other meds for inpatient and outpatient use.
- medRxiv Published online June 16, 2021; doi:10.1101/2021.06.15.21258542
- medRxiv Published online May 28, 2021; doi:10.1101/2021.05.27.21257096
- medRxiv Published online June 6, 2021; doi:10.1101/2021.05.19.21257469
- www.idsociety.org/globalassets/idsa/practice-guidelines/covid-19/treatment/idsa-covid-19-gl-tx-and-mgmt-v4.4.1.pdf (7-30-21)
- www.covid19treatmentguidelines.nih.gov/therapies/statement-on-anti-sars-cov-2-monoclonal-antibodies-eua/ (7-30-21)