Safety and efficacy of a novel anti-CD20/CD19 bi-specific CAR T-cell therapy (C-CAR039) in relapsed or refractory (r/r) B-cell non-Hodgkin lymphoma (B-NHL).
Authors: Aibin Liang, Lili Zhou, Ping Li, Wenjuan Yu, Min Yang, Yangyang Xu, Shiguang Ye, Judy Zhu, Jiaqi Huang, Yan Zhang, Lanfang Li, Jing Zhao, Jing Li, Chengxiao Zheng, Kevin Zhu, Liping Lan, Huilai Zhang, Daobin Zhou, Yihong Yao, Jie Jin
Journal: Journal of Clinical Oncology (2021)

2507 Background: C-CAR039 has been developed as a novel 2nd generation 4-1BB bi-specific CAR-T targeting both CD19 and CD20 antigens with an optimized bi-specific antigen binding domain. C-CAR039 can eradicate CD19/CD20 single or double positive tumor cells in vitro and in vivo. The tissue cross reactivity and whole genome membrane proteome array studies further confirmed the specificity of C-CAR039. Methods: GMP manufacturing of C-CAR039 was carried out in a serum free and fully closed semi-automatic system. Dose escalation and expansion studies were conducted to evaluate the safety and efficacy of C-CAR039 in r/r B-NHL patients. C-CAR039 was administered as a single intravenous dose after a 3-day cyclophosphamide plus fludarabine conditioning regimen. Results: As of 1/31/2021, 28 patients were infused and 25 (DLBCL, n = 22; PMBCL, n = 1; tFL, n = 1; FL, n = 1) were evaluable for safety and efficacy at dose ranges of 1.0 x 10 6 to 5.0x10 6 CAR-T cells/kg. The median age was 54 (range, 28-71) years, median number of prior lines of therapy was 3 (range, 1–5), 76% (19/25) of patients were in Ann Arbor Stage III/IV, and 80% (20/25) were refractory to their last treatment. 5 patients (20%) received bridging therapy. Cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) were graded according to ASTCT 2019 criteria. Of the 25 patients, 24 (96%) experienced CRS, 23 (92%) were grade 1 or 2, 1 patient was grade 3. Median time to onset of CRS was 3 days (range, 0-10), with median duration of 4 days (range, 1-25). 2 patients had a grade 1 ICANS. Grade≥3 neutropenia, anemia, thrombocytopenia and infection were reported in 88%, 40%, 16% and 0% of patients, respectively. The best overall response rate was 92%, complete response (CR) rate was 84% and median time to response was 1.0 month (range, 0.9-1.2). With a median follow-up of 5.3 months, 76% remained in CR. Kaplan Meyer estimation of PFS at 6 months was 87.3% (95% CI, 71.2 to 100.0). Median duration of response has not been reached. Furthermore, C-CAR039 showed an encouraging cellular kinetic profile. In 25 evaluable patients, the median T max was 11 day, the median C max was 139,497 copies/mg gDNA, and the median AUC 0̃28DAY of 1,673,844 day*copies/μg gDNA. Conclusions: C-CAR039 demonstrated a favorable safety profile and promising efficacy in this early clinical trial in patients with r/r B-NHL that might allow it to differentiate from existing therapies. The early clinical efficacy signal is encouraging and compares favorably to anti-CD19 CAR-T and peer therapies. These findings will be evaluated in more patients with longer follow-up to confirm safety, efficacy and duration of response. Clinical trial information: NCT04317885 , NCT04655677 , NCT04696432 , NCT04693676 .