MM:New Tool Gauges Post–CAR T Relapse Risk
FROM THE 6TH EUROPEAN CAR T-CELL MEETING
“To our knowledge, this large multicenter study is the first report to identify patients with RRMM at high risk of early relapse after CAR-T,” the authors report in the study, published February 15 in the Journal of Clinical Oncology.
“We saw that early relapse within 5 months from infusion was significantly associated with very poor outcomes, and disease-, treatment-, and inflammation-specific variables were independent predictors of early relapse,” first author Nico Gagelmann, MD, of the University Medical Center Hamburg-Eppendorf, in Hamburg, Germany, explained in presenting the findings at the 6th European CAR T-cell Meeting jointly sponsored by the European Society for Blood and Marrow Transplantation and the European Hematology Association. CAR-T therapy has revolutionized the treatment of RRMM, with the idecabtagene vicleucel (ide-cel) and ciltacabtagene autoleucel (cilta-cel) CAR-T therapies approved for the condition. However, the treatment is far from a cure, with nearly 50% of patients relapsing and having progression of disease within the first year after infusion, prompting a need to better understand the risk factors for who may or may not progress.
With a lack of a universal model to help with those predictions across products and populations, Dr. Gagelmann and colleagues conducted a retrospective observational study utilizing data from 136 patients at seven CAR-T centers in Europe and 133 patients at three centers in the US who had received either commercial or academically produced anti-BCMA CAR-T.
Of the patients, 171 were infused with ide-cel, 38 with cilta-cel, and 60 with an academic CAR-T therapy. The patients had a median age of 63, and extramedullary disease was more common in the US cohort (48%) versus European (35%; P = .04).
Notably, the response rates between the European and US cohorts were similar, despite various differences between the cohorts, including differences in ethnicities and a lower body mass index (BMI) in the European cohort versus US (BMI 25 vs 28, respectively; P < .001). There were also no significant differences in responses between the CAR-T treatments.
The overall response rate was 87% and was comparable between the European and US groups, with complete responses occurring among 48% of patients in Europe and 49% in the US group.
Their measurable residual disease (MRD) negativity rate at any time was 29% and 37%, respectively, and rates of complete response at day 30 were 29% and 26%, respectively. The rate of progression-free survival at 12 months was 40% for the entire cohort, with a rate of 45% in the European group and 34% in the US group (P = .09). Overall survival rates at 12 months were 79% and 65%, respectively (P = .11).
The patients had a median time to relapse of 5 months, and the 5-month incidence of relapse was identical, at 24% in each cohort.
Of those patients, overall survival at 12 months was low, at 30% in the European cohort and 14% in the US group.
“Early relapse within the first 5 months clearly identified patients with poor survival across the cohort,” Dr. Gagelmann said.
