BCMA Targeted Therapies and Their Impact on Outcomes in Relapsed or Refractory Multiple Myeloma: Results From the French EMMY Cohort

Objectives B‐cell maturation antigen (BCMA)‐targeted therapies have recently transformed the management of relapsed or refractory multiple myeloma (RRMM). This study aimed to evaluate their implementation and real‐world impact within EMMY, a French longitudinal cohort. Methods Patients initiating a fourth or later line of therapy (L4+) between 2017 and 2023 across 73 centers were included. Temporal trends in treatment use were described. Outcomes, including progression‐free survival (PFS) and time to next treatment (TTNT), were compared between patients treated with BCMA‐targeted therapies and other regimens. Analyses were performed at the patient level and at the treatment‐line level. Safety data were not collected. Results Among 1362 patients treated in L4+, 294 (21.6%) received a BCMA‐targeted regimen. Use increased from 2.4% in 2019 to 52.0% in 2023, driven by bispecific antibodies. Outcomes improved over time, with median TTNT rising from 8.0 months in 2017 to 12.1 months in 2022, and median PFS from 7.2 to 9.3 months. In L4, BCMA‐targeted therapies were associated with longer TTNT (21.7 vs. 9.3 months; p = 0.007) and PFS (13.4 vs. 7.9 months; p = 0.015). Similar trends were observed in later lines. Conclusions BCMA‐targeted therapies were rapidly integrated into real‐world practice and were associated with improved outcomes in late‐line RRMM.