The chimeric antigen receptor (CAR) T-cell therapy ciltacabtagene autoleucel may offer benefit in patients with multiple myeloma who experienced disease progression or relapse following initial therapy, according to new findings presented by Hillengass et al at the 2024 Tandem Meetings: Transplantation & Cellular Therapy Meetings of the American Society for Transplantation and Cellular Therapy and Center for International Blood and Marrow Transplant Research (Abstract 42).
Background
In 2022, the U.S. Food and Drug Administration approved ciltacabtagene autoleucel—a CAR T-cell therapy that targets the B-cell maturation antigen (BCMA) expressed on multiple myeloma cells but not on most other cells—to treat patients with relapsed or refractory multiple myeloma who received at least four lines of prior therapy.
Study Methods and Results
In the phase II CARTITUDE-2 trial (ClinicalTrials.gov identifier NCT04133636), researchers evaluated the safety and efficacy of ciltacabtagene autoleucel in 169 patients with multiple myeloma whose disease had progressed less than 1 year following autologous stem cell transplant or who experienced relapse following up to three lines of initial therapy. The patients were assigned to eight different cohorts with different characteristics. They noted that patients in cohort A (n = 20) received between one and three prior lines of therapy and patients in cohort B (n = 19) experienced disease relapse within 1 year of either autologous stem cell transplant or the start of initial anti–multiple myeloma treatment.
The researchers demonstrated that a single infusion of ciltacabtagene autoleucel resulted in deep, durable responses in the patients. After a median follow-up of 29.9 months, the researchers performed a highly sensitive test on bone marrow samples and revealed that 85.0% (n = 17) of the patients from cohort A were measurable residual disease (MRD)-evaluable, and 100% of them achieved undetectable MRD. After a median follow-up of 27.9 months, they discovered that 78.9% (n = 15) of the patients in cohort B were MRD-evaluable, and 93.3% (n = 14) of them achieved undetectable MRD.
Further, the patients in cohort A achieved overall response rates of 95% (complete response or better, 90%), and the patients in cohort B achieved overall response rates of 100% (complete response or better, 89.5%). The median progression-free survival was not reached in either cohort, and 24-month progression-free survival rates were 75% in cohort A and 73% in cohort B.
Ciltacabtagene autoleucel was well tolerated in both cohorts. The most common side effects included cytokine-release syndrome, immune cell–associated neurotoxicity, and hematologic toxicity.
Conclusions
“We’re very excited to see how well CAR T cells work in earlier lines of therapy, because we think the T cells used to manufacture the CAR T cells are less exhausted when they are collected in earlier lines compared [with] late lines of therapy,” highlighted lead study author Jens Hillengass, MD, PhD, Chief of Myeloma and Vice Chair for Research at the Roswell Park Comprehensive Cancer Center.
The researchers plan to continue assessing the potential of anti-BCMA CAR T-cell therapy administered in earlier lines of therapy—with a goal of improving patients’ treatment response and survival outcomes. Researchers at the Roswell Park Comprehensive Cancer Center is currently participating in the phase II, multicenter BMTCTN 1902 trial (ClinicalTrials.gov identifier NCT05032820) exploring bb2121 anti-BCMA CAR T-cell therapy in patients who have had a suboptimal response following autologous stem cell transplant and 3 months of maintenance therapy.
Disclosure: For full disclosures of the study authors, visit tandem.confex.com.
