ASH 2020 | SC vs. IV administration of a BCMA-CD3 bispecific antibody for R/R myeloma

Alexander Lesokhin, MD, Memorial Sloan-Kettering Cancer Center, New York, NY, shares the preliminary results of a Phase I study (NCT03269136) of PF-3135, a bispecific monoclonal antibody, in relapsed/refractory (R/R) multiple myeloma. PF-3135 is targeted to BCMA, an antigen that is highly expressed on the surface of myeloma cells. It additionally targets T-cell expressed-CD3 and, through this, can exert T-cell cytotoxic activity against myeloma cells. The study trialed subcutaneous (SC) administration of the drug, given its potential to reduce the maximum concentration and associated cytokine release syndrome (CRS) occurrence. The dose-escalation stage proved PF-3135 to be safe, with manageable adverse events and no dose-limiting toxicities. The overall response rate was significantly higher in patients receiving the highest two dose levels, compared to that of all four doses combined. The effect of SC dosing on the maximum concentration allowed the use of higher doses than IV, without increasing CRS severity. This interview took place during the 62nd American Society of Hematology (ASH) Annual Meeting and Exposition, 2020.