Single-center phase 2 trial of anti-GPRC5D CAR T-cell therapy for progressive multiple myeloma after anti-BCMA CAR T-cell therapy

For patients with multiple myeloma progressing after anti-BCMA CAR T-cell therapy, the optimal salvage treatment strategies are not clear. A phase 2 trial at the Affiliated Hospital of Xuzhou Medical University (Xuzhou, China) evaluated anti GPRC5D CAR T-cell therapy for these patients. At a median follow-up of 12.6 months (IQR 8.2-20.8), the overall response rate (primary endpoint) was 84% (95% CI 68-94), including 35% with complete response or better. The most common grade 3 or 4 adverse events were hematologic toxicities. Cytokine release syndrome occurred in 70%; grade 3 in 5%. One case of grade 1 immune effector cell-associated neurotoxicity syndrome was observed. There were no treatment-related deaths in the trial. The authors conclude that anti-GPRC5D CAR T-cell salvage therapy induced a high response rate, and could be a treatment option in relapsed or refractory multiple myeloma patients with progression after anti-BCMA CAR T-cell treatment.