Immunobridging for Pemivibart, a Monoclonal Antibody for Prevention of Covid-19

This correspondence outlines the immunobridging methodology used to support the Emergency Use Authorization (EUA) of pemivibart, a monoclonal antibody for preexposure prophylaxis of Covid-19 in immunocompromised individuals. The CANOPY trial (NCT06039449) evaluated pemivibart’s neutralizing titers against the JN.1 variant and compared them to protection thresholds derived from adintrevimab, which had shown efficacy against the delta variant in the EVADE trial. Two immunobridging methods were employed: one using direct extrapolation from adintrevimab’s pharmacokinetics and IC50 values, and another based on a meta-analysis of monoclonal antibody efficacy curves. Pemivibart achieved a geometric mean titer (GMT) of 6278 at day 28, with an immunobridging ratio of 0.70 (90% CI, 0.68–0.72), meeting the predefined threshold. Adverse events included infusion-related reactions (8.2%) and anaphylaxis (0.6%). The authors advocate for immunobridging as a viable regulatory pathway for monoclonal antibodies targeting emerging SARS-CoV-2 variants.

This correspondence outlines the immunobridging methodology used to support the Emergency Use Authorization (EUA) of pemivibart, a monoclonal antibody for preexposure prophylaxis of Covid-19 in immunocompromised individuals. The CANOPY trial (NCT06039449) evaluated pemivibart’s neutralizing titers against the JN.1 variant and compared them to protection thresholds derived from adintrevimab, which had shown efficacy against the delta variant in the EVADE trial. Two immunobridging methods were employed: one using direct extrapolation from adintrevimab’s pharmacokinetics and IC50 values, and another based on a meta-analysis of monoclonal antibody efficacy curves. Pemivibart achieved a geometric mean titer (GMT) of 6278 at day 28, with an immunobridging ratio of 0.70 (90% CI, 0.68–0.72), meeting the predefined threshold. Adverse events included infusion-related reactions (8.2%) and anaphylaxis (0.6%). The authors advocate for immunobridging as a viable regulatory pathway for monoclonal antibodies targeting emerging SARS-CoV-2 variants.