Abstract CT244: HR001, a novel CD19-targeted CAR-T cell therapy for patients with relapsed/refractory non-Hodgkin's lymphoma: primary results of a phase II study (HRAIN01-NHL01-II)

Abstract Background: HR001 is a CD19-targeted CAR-T cell for patients with relapsed and refractory non-Hodgkin's (R/R NHL). Here, we report the primary results of the phase 2 study (HRAIN01-NHL01-II). Methods: HRAIN01-NHL01-II is an open-label, single-arm, and multicenter (17 centers) study in China. It enrolled R/R NHL patients treated with at least two lines of therapy (must-have anthracycline and CD20-targeted agents) or after autologous hematopoietic stem cell transplantation. All patients received a single infusion of HR001 at the 2.0 × 106 CAR+T cells/kg dose. The disease response was evaluated by the independent review committee with Lugano response criteria [2014]. Results: As of May 16th, 2023, 81 R/R NHL patients with ECOG 0-1 at baseline received the infusion HR001 from the Jinshan manufacturing facility [51.9% male; median age 53.4 years (range 23~74); 3.7% CD19 negative; 91.4% diffuse large B-cell lymphoma; 79.0% III-IV of Ann Arbor classification or Lugano] with a median follow-up of 160 days (range 7 to 454). The median time to best response was 30 days (range 28-358). The 3-month, 6 month and best objective response rate (ORR) was 53.1%(95% CI: 41.7-64.3), 45.7%(95% CI: 34.6-57.1) and 74.1% (95% CI: 63.1-83.2) respectively. The 3-month, 6 month and best complete response rate (CRR) was 32.1%(95% CI: 22.2-43.4), 29.6%(95% CI: 20.0-40.8) and 49.4%(95% CI: 38.1-60.7) respectively. Median duration of response (DOR) and progression-free survival (PFS) were 339 days (95% CI: 149-NE) and 176 days (95% CI: 91-NE) respectively. The overall survival (OS) was not reached. The most common treatment-related adverse events (AEs) happened in the hematologic system. The cytokine release syndrome (CRS) occurred in 95.1% of patients, with ≥3 grade CRS observed in 3.7% of patients. Immune effector cell-associated neurotoxicity syndrome (ICANS) happened in 8.6% of patients, without any ≥ 3 grade ICANS reported. The treatment-related mortality was 1.2%. The median time to CAR T-cell peak expansion was 240 hours (120~672) after infusion, median maximum expansion (Cmax) was 17413.9 copies/μg DNA (124.9~136382.2), and median AUC0-28d was 3201014.0 copies/μg DNA (205082.8~18400016.2). Positive tests for the anti-drug antibody (ADA) were noted in 14.8% of patients, while neutralizing antibody (Nab) tests were positive in 3.7% of patients. Among Nab-positive patients, the complete response was maintained until follow-up. Conclusions: Patients with R/R NHL could benefit from the HR001 treatment with satisfactory objective response, durable remission, and favorable safety profile. Citation Format: Yian Zhang, Yuhua Li, Kai Hu, Wuping Li, Hongwei Xue, Qi Deng, Zheng Ge, Liangquan Geng, Xianmin Song, Kang Yu, Hongmei Jing, Bing Chen, Xin Li, Zhimin Zhai, Jianping Shen, Jiang Cao, Qingming Wang, Peng Liu. HR001, a novel CD19-targeted CAR-T cell therapy for patients with relapsed/refractory non-Hodgkin's lymphoma: primary results of a phase II study (HRAIN01-NHL01-II) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT244.