CARsgen Therapeutics Holdings Limited presented compelling long-term follow-up data for its BCMA-targeting CAR T-cell therapy zevor-cel at the 22nd International Myeloma Society Annual Meeting, demonstrating exceptional efficacy and safety in patients with relapsed or refractory multiple myeloma after nearly five years of follow-up.
Remarkable Response Rates and Durability
The Phase I clinical trial enrolled 14 patients with relapsed or refractory multiple myeloma who received a single infusion of zevorcabtagene autoleucel (zevor-cel). With a median follow-up duration of 53.3 months as of February 22, 2025, the therapy achieved a 100% overall response rate (95% CI: 76.8, 100.0), with 11 patients (78.6%) achieving complete response or stringent complete response.
All patients who achieved complete response or better demonstrated minimal residual disease negativity at the 10⁻⁵ threshold, indicating deep molecular remissions. Notably, one patient remained in stringent complete response at 59.3 months, highlighting the potential for long-term disease control.
Sustained Clinical Benefits
The median progression-free survival and median duration of response in patients achieving complete or stringent complete response were 44.1 months and 43.2 months, respectively. The median overall survival has not been reached, underscoring the therapy's potential for long-term patient benefit.
Survival analysis revealed impressive durability, with 100% of patients surviving at 24 months post-infusion, 92.3% at 36 months, 84.6% at 48 months, and 76.9% at 60 months. These results represent some of the longest follow-up data available for BCMA-targeting CAR T-cell therapies in multiple myeloma.
Favorable Safety Profile Maintained
The long-term safety profile remained manageable throughout the extended follow-up period. Critically, there were no reports of Grade 3 or higher cytokine release syndrome, immune effector cell-associated neurotoxicity syndrome, delayed neurotoxicities, second primary malignancies, or other delayed adverse events.
This safety profile is particularly noteworthy given the extended observation period, addressing concerns about long-term toxicities that can emerge with CAR T-cell therapies.
Regulatory Milestones and Clinical Context
Zevor-cel, a fully human autologous BCMA CAR T-cell product, received approval from China's National Medical Products Administration on February 23, 2024, for treating adult patients with relapsed or refractory multiple myeloma who have progressed after at least three prior lines of therapy, including a proteasome inhibitor and an immunomodulatory agent.
The therapy previously received both Regenerative Medicine Advanced Therapy and Orphan Drug designations from the U.S. FDA in 2019, reflecting regulatory recognition of its potential to address unmet medical needs in multiple myeloma treatment.
CARsgen has established comprehensive capabilities spanning target discovery, preclinical research, clinical development, and commercial-scale production, positioning the company to address key challenges in CAR T-cell therapy including safety optimization, enhanced efficacy in solid tumors, and cost reduction.
