Phase 2 Study of Relmacabtagene Autoleucel (CD19 CAR-T) for Relapsed/Refractory Mantle Cell Lymphoma in Chinese Adults

Abstract

Relma-cel, an anti-CD19 CAR-T therapy, is approved in China for R/R large B-cell lymphoma and follicular lymphoma. This phase 2, open-label, single-arm, multicenter study evaluated its efficacy and safety in Chinese patients with heavily pretreated R/R mantle cell lymphoma. A total of 70 patients with R/R MCL who had undergone 1-9 prior therapies (including anthracycline or bendamustine chemotherapy, anti-CD20 antibodies, and BTK inhibitors) were enrolled. Of these, 59 received a single infusion of 100×10⁶ CAR+ T cells following leukapheresis. The primary endpoint was the objective response rate (ORR) at 3 months post-infusion, assessed using Lugano 2014 criteria. Secondary endpoints included duration of response (DOR), progression-free survival (PFS), overall survival (OS), and safety. At 3 months, the ORR was 71.19% (95% CI: 57.92-82.24), with a complete response (CR) rate of 59.32% (95% CI: 45.75-71.93). After a median follow-up of 13.3 months (95% CI: 9.04-18.69), the median DOR was 18.1 months, PFS was 15.5 months, and OS was 19.5 months. Grade 3 or higher treatment-emergent adverse events (TEAEs) were common, including neutropenia (76.3%), leukopenia (69.5%), and lymphopenia (47.5%). Severe cytokine release syndrome (CRS) and neurotoxicity (NT) occurred in 6.8% of patients each, with all cases resolving fully. No fatal events were reported. These findings demonstrate that relma-cel offers high response rates, durable remissions, and manageable safety in Chinese patients with R/R MCL. This trial was registered at www.clinicaltrials.gov as # NCT04718883.