Abstract 1652: Binding to bridging: Complete suite of FcγR assay tools accelerates antibody therapeutic development

Abstract Antibodies are effective therapeutics because of their specificity in binding to an antigen and ability to activate an immune response through Fc effector functions like antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cell phagocytosis (ADCP), and complement-dependent cytotoxicity (CDC) by engaging with immune cells like NK cells and macrophage. However, traditional methods for characterizing these interactions are highly variable and labor-intensive. We developed a suite of luminescent assays for characterizing antibody effector functions for robust, streamlined measurement across antibody development: Lumit® Binding Immunoassays, Fc Effector Reporter Bioassays for ADCC/ADCP, and HiBiT Target Cell Killing Bioassays using MoA-qualified primary cells. We demonstrate application to anti-CD20 biosimilar antibodies, showing concordant rank order from binding to functional killing studies. These rapid, high-throughput assays support comparability, stability, and lot-release decisions. Citation Format: Julia K. Gilden, Denise Garvin, Kristin Riching, Brock F. Binkowski, Richard Moravec, Pete Stecha, Rod Flemming, Becky Godat, Kai Hillman, Marjeta Urh, Mei Cong, Jamison Grailer, . Binding to bridging: Complete suite of FcγR assay tools accelerates antibody therapeutic development [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 1652.