Dr Bal on the Investigation of BMS-986393 in R/R Multiple Myeloma

Susan Bal, MD, assistant professor, Hematology, Medical Oncology, University of Alabama at Birmingham (UAB), UAB Health, O’Neal Comprehensive Cancer Center, discusses updated safety and efficacy data from the dose-escalation and dose-expansion portions of phase 1 trial (NCT04674813) of the GPRC5D-targeted autologous CAR T-cell therapy BMS-986393 (CC-95266) in patients with relapsed/refractory multiple myeloma.

The first-in-human, multicenter, open-label study is evaluating the CAR T-cell therapy in patients with relapsed/refractory disease who received 3 or more prior lines of therapy. After lymphodepletion, patients received a single infusion of BMS-986393. During dose escalation, patients were given 1 of 5 dose levels, ranging from 25 x 106 CAR T cells to 450 x 106 CAR T cells. In dose expansion, patients were treated at 150 x 106 CAR T cells, 300 x 106 CAR T cells, or 450 x 106 CAR T cells. The primary end points were safety and to determine a maximum tolerated dose and the recommended phase 2 dose.

As of March 2023, 52 patients were evaluated for efficacy, and the overall response rate (ORR) across all doses was 86.5%, including a complete response (CR) or better rate of 38.5%, Bal says. Notably, nearly half (n = 25) of these patients had received a prior BCMA-directed therapy, Bal adds. In the subset of patients who had received prior treatment with a BCMA-directed therapy, the ORR was 76.0% with a CR or better rate of 36.0%. In patients who had not received prior BCMA-directed therapy, the ORR was 96.3%.

The ORR data were encouraging, irrespective of whether patients had been exposed to prior BCMA-directed therapy, Bal continues. Although the minimal residual disease (MRD) data were immature, she noted that all 6 patients who were evaluable for efficacy and MRD were MRD negative at month 3.