On June 3, the Food and Drug Administration (FDA) issued a revised emergency use authorization (EUA) for a lower dose of REGEN-COV (600 mg casirivimab and 600 mg imdevimab), which is half the dose originally authorized. Though intravenous (IV) infusion is strongly recommended for administration of REGEN-COV, guidance has been updated to allow for subcutaneous injection when IV infusion is not feasible and would lead to delays in treatment. The single vial of co-formulated product is now available for order via AmerisourceBergen.
The Federal Response to COVID 19: Monoclonal Antibody Playbook has been updated to reflect the above and to also note that previously shipped REGEN-COV contains two doses as of the June 3, 2021 EUA. While the previously shipped dose pack may be used for two doses, the guidance notes that once punctured, the vials should be discarded after four hours. The EUA for REGEN-COV has also been updated to include information for efficacy against variants of concern (please see section 15 of the EUA) and notes that REGEN-COV is likely to retain activity against the Beta (B.1.351) and Gamma (P.1) variants.