Talquetamab in relapsed refractory multiple myeloma: multi-institutional real-world study

Talquetamab is a first-in-class GPRC5DxCD3 bispecific antibody approved for heavily pretreated relapsed/refractory multiple myeloma (RRMM), and this multicenter retrospective analysis of 114 RRMM patients treated between October 2023 and January 2025 demonstrated significant efficacy in a heavily pretreated population with median 6 prior therapies. All patients were triple-class refractory, 79% were penta-refractory, and 65% had received prior BCMA-targeted therapy. The overall response rate was 73%, including complete response in 26% and very good partial response in 26%, with six-month progression-free and overall survival rates of 56 and 86% respectively and median progression-free survival of 10 months. Common adverse events included cytokine release syndrome (CRS; 54% with grade ≥2 in 7.3%), infections (27%), and immune effector cell-associated neurotoxicity syndrome (9.8%). The 3-month cumulative infection incidence of 14% for both bacterial and viral infections, where 59% were viral and 41% bacterial, grade ≥3 infections occurred in 18%, and intravenous immunoglobulin was used in 61% of patients. Significant weight loss was observed, with a mean 8.8% decrease at 6 months. This real-world analysis confirms talquetamab's efficacy in heavily pretreated RRMM while highlighting notable toxicities, including progressive weight loss and infections, which require rigorous monitoring and proactive supportive care.