RADIATION THERAPY AS A BRIDGING AND SALVAGE STRATEGY IN PATIENTS WITH RELAPSED OR REFRACTORY MULTIPLE MYELOMA UNDERGOING BCMA‐TARGETED CAR T‐CELL THERAPY

Introduction: Radiation therapy (RT) may be a useful bridging and/or salvage approach prior to and following B-cell maturation antigen (BCMA)-targeted chimeric receptor (CAR) T-cell in patients with relapsed or refractory multiple myeloma (MM). Thus, we sought report our early experience evaluating the potential role of RT settings MM undergoing CAR therapy. Methods: A multi-institutional retrospective study was conducted for consecutive who received between 2018 2022. Patients were administered pre-CAR T post-CAR failure identified analyzed using descriptive statistical analysis. Results: We retrospectively reviewed 13 have been treated pre- infusion at two tertiary care centers [5 T, 4 failure, both RT]. total 17 sites bridging-RT median dose 20 Gy (range, 4–24 Gy) 5 fractions 1–12 fractions). Twelve dose/fractionation 4–30 No worsening T-related toxicities occurred among RT, no significant RT-related observed post-bridging RT. For entire cohort, overall survival 16.2 months (95% CI: 8.6 months-not reached), progression-free 4.1 1.07 reached). The local control rate receiving 100%, follow-up after each course 7.3 months. Conclusion: Our findings suggest that as strategy is safe feasible, offers excellent relapsed/refractory infusion. Future larger studies translational correlatives are required assess optimal these settings. Keywords: Cellular therapies, Multiple Myeloma conflicts interests pertinent abstract.