Immunobridging for Pemivibart, a Monoclonal Antibody for Prevention of Covid-19
Peter Schmidt, Yong Li, Myra Popejoy
Abstract
Immunobridging for Pemivibart, a Monoclonal Antibody for Prevention of Covid-19To the Editor: On March 22, 2024, the Food and Drug Administration issued Emergency Use Authorization (EUA) for the monoclonal antibody pemivibart as preexposure prophylaxis for Covid-19 in certain adults and adolescents with moderate-to-severe immunocompromise.The EUA was issued on the basis of safety and immunobridging data from the CANOPY trial (ClinicalTrials.govnumber, NCT06039449), which included two cohorts: an open-label cohort of 306 persons with moderate-to-severe immunocompromise, who received an initial intravenous infusion of a single 4500-mg dose of pemivibart followed by a second infusion at the same dose approximately 90 days later, and a placebo-controlled cohort of persons without immunocompromise, who were randomly assigned to receive either pemivibart or placebo on the same schedule.Additional information is provided in the protocol and Supplementary Appendix, both of which are available with the full text of this letter at NEJM.org.The analysis of the primary end point was performed by means of an immunobridging method, which allowed for a comparison of the neutralizing antibody titers calculated for pemivibart with those calculated for the monoclonal antibody adintrevimab.Adintrevimab had shown efficacy against the B.1.617.2 (delta) variant but