Claudin18.2-targeted chimeric antigen receptor T cell-therapy for patients with gastrointestinal cancers: Final results of CT041-CG4006 phase 1 trial.
Authors: Changsong QI, Chang Liu, Jifang Gong, Jian Li, Dan Liu, Xicheng Wang, Panpan Zhang, Yanru Qin, Miao Zhang, Zhi Peng, Jun Zhou, Xiaotian Zhang, Xiaohui Peng, Yumeng Wang, Zijing Zhang, Daijing Yuan, Zhen Liu, Raffaele Baffa, Zonghai Li, Lin Shen
Journal: Journal of Clinical Oncology (2024)

2501 Background: Autologous anti-claudin18.2 (CLDN18.2) CAR T cell, satricabtagene autoleucel (satri-cel)/CT041, was investigated in gastrointestinal cancers in clinical trials. The interim results of CT041-CG4006 trial (NCT03874897) were published in June 2022 [1] . Herein, we present the final results of this trial. Methods: This single-arm, open-label, phase 1 trial evaluated the safety and efficacy of CT041 in patients (pts) with CLDN18.2-positive advanced gastrointestinal (GI) cancers. The trial consisted of a dose-escalation (250×10 6 , 375×10 6 , 500×10 6 or 1000×10 6 cells) using modified ‘3+3’ design and dose expansion of CT041 in 4 cohorts (Cohort 1: CT041 in pretreated pts with advanced GI cancers, Cohort 2: CT041 plus anti-PD-1 therapy in pretreated pts with advanced GI cancers, Cohort 3: CT041 sequential treatment following first-line therapy in gastric cancer (GC) and Cohort 4: CT041 in pts with prior failure to anti-CLDN18.2 antibody). The primary endpoint was safety; secondary endpoints were efficacy using RECIST v1.1, pharmacokinetics, and immunogenicity. Results: From 26 March 2019 to 26 January 2024, a total of 98 pts received CT041 infusion, including GC (n=73), pancreatic cancer (n=10), biliary tract cancer (n=4), intestinal cancer (n=8) and other tumors (n=3). A total of 89 pts were dosed with 250×10 6 , 6 pts with 375×10 6 , and 3 pts with 500×10 6 cells, with a median follow-up of 29.7 (range: 1.2, 35.5) months. 250×10 6 was selected for the dose-expansion stage based on the dose-escalation results. The most commonly reported treatment-emergent adverse events of grade 3 or higher were hematologic toxicity related to lymphodepletion. No dose-limiting toxicities, treatment-related deaths, or immune effector cell-associated neurotoxicity syndrome were reported. Cytokine release syndrome occurred in 96.9% of pts, all classified as grade 1-2. Gastric mucosal injuries were identified in 8 (8.2%) pts, including 7 cases of grade 1-2 and 1 case of grade 3 gastritis erosive which recovered. For all pts (N=98), the ORR and DCR reached 37.8% and 75.5%, respectively. The median PFS and median OS were 4.4 (95% CI: 4.0, 6.0) months and 8.4 (95% CI: 7.0, 10.0) months for all pts. Among efficacy evaluable GC pts who received CT041 monotherapy, the ORR and DCR in those with measurable disease (n=47) reached 57.4% and 83.0%, respectively, and the median PFS and median OS in all efficacy evaluable GC pts (n=55) were 5.8 (95% CI: 4.2, 8.4) months and 9.7 (95% CI: 7.1, 14.4) months, respectively. Conclusions: Satri-cel/CT041 demonstrated a promising safety profile and highly encouraging efficacy in heavily pretreated patients with CLDN18.2-positive advanced GI cancers. Clinical trial information: NCT03874897 .