CARsgen Therapeutics announced that long-term follow-up results of its Claudin18.2-targeted CAR-T cell therapy, Satricabtagene Autoleucel (Satri-cel, CT041), were presented at the 2026 Annual Meeting of the American Society of Clinical Oncology (ASCO). The poster presentation, titled “Long-term Follow-up of Satricabtagene Autoleucel (Satri-cel) as Sequential Therapy After First-Line Treatment for Advanced Gastric Cancer – A Subgroup Analysis,” highlighted encouraging efficacy and safety outcomes in patients with advanced gastric cancer (GC) and gastroesophageal junction adenocarcinoma (GEJA).
Background of the study
The data originated from the investigator-initiated clinical trial CT041-CG4006 (NCT03874897), an open-label, multi-cohort Phase I study evaluating Satri-cel in patients with Claudin18.2-positive advanced gastrointestinal cancers.
Earlier results from the study were published in Nature Medicine and presented at previous ASCO meetings. The latest analysis focused on Cohort 3, providing more than 4.5 years of follow-up, making it one of the longest reported follow-up periods for a CAR-T therapy in advanced gastric cancer.
Patient characteristics
The cohort included five patients with Claudin18.2-positive gastric or gastroesophageal junction cancer. These patients had particularly aggressive disease characteristics associated with poor prognosis:
- 60% had Lauren diffuse-type gastric cancer
- 20% had mixed histology
- 80% had signet-ring cell carcinoma
- 80% had peritoneal metastases
Before receiving Satri-cel, patients underwent first-line treatment for a median of five cycles (range 4–11 cycles). Only one patient achieved a partial response from first-line therapy, indicating limited benefit from conventional treatment.
Remarkable long-term outcomes
Following first-line therapy, all five patients received a single infusion of Satri-cel at a dose of 2.5 × 10⁸ CAR-T cells.
As of October 18, 2025, the median follow-up from initiation of first-line treatment reached 54.6 months.
Among the four patients with measurable target lesions:
- Confirmed objective response rate (ORR): 100%
- Median duration of response (DOR): Not reached
The fifth patient, who did not have measurable target lesions at baseline, maintained stable disease for 20.9 months.
Additional outcomes included:
- Median progression-free survival (PFS): 20.9 months
- Two patients achieved sufficient tumor reduction to undergo surgical resection after Satri-cel treatment
- Both surgically treated patients remained alive at data cutoff, with follow-up durations of 58.1 months and 51.1 months, respectively
These findings suggest that Satri-cel may not only provide durable disease control but could also potentially convert selected advanced gastric cancer patients to surgical candidates.
Favorable safety profile
The long-term analysis also demonstrated a manageable safety profile:
- No Grade 3 or higher cytokine release syndrome (CRS)
- No immune effector cell-associated neurotoxicity syndrome (ICANS)
- No treatment-related deaths
- No Grade 3 or higher infections
- No febrile neutropenia events
The safety findings were consistent with previous reports and support the feasibility of Satri-cel in this patient population.
Implications for gastric cancer treatment
Advanced gastric cancer and gastroesophageal junction cancer remain challenging diseases with limited long-term survival outcomes, especially among patients with diffuse-type histology, signet-ring cell carcinoma, and peritoneal metastases.
With more than 4.5 years of follow-up, Satri-cel demonstrated durable responses, prolonged progression-free survival, and encouraging overall survival signals in a group of patients with historically poor prognostic features. The results further strengthen the growing evidence supporting Claudin18.2-targeted CAR-T therapy as a promising treatment strategy for gastric cancer.
As the world’s first approved CAR-T therapy targeting a solid tumor, Satri-cel continues to establish a new treatment paradigm and may play an increasingly important role in earlier lines of therapy for Claudin18.2-positive gastric and gastroesophageal junction cancers.
