A prospective, single-arm, phase II study to evaluate the efficacy and safety of perioperative tislelizumab in resectable non-small-cell lung cancer (NSCLC).

Abstract

8049 Background: Perioperative immunotherapy has emerged as a promising strategy for the treatment of resectable non-small cell lung cancer (NSCLC). This study was designed to evaluate the efficacy and safety of a comprehensive perioperative regimen, comprising neoadjuvant tislelizumab in combination with chemotherapy, followed by surgical resection and adjuvant tislelizumab, in patients with resectable stage II-IIIB NSCLC. Methods: This open-label, single-arm, phase 2 trial was designed to enroll patients (pts) with resectable stage II-IIIB (N2) NSCLC (AJCC 8 th edition). Participants received neoadjuvant therapy consisting of intravenous tislelizumab in combination with chemotherapy administered every 3 weeks for 2 to 4 cycles prior to surgery, and 0 to 2 cycles following surgery (totaling up to 4 cycles of perioperative therapy). This was followed by adjuvant tislelizumab monotherapy administered Q3W for 1 year. The primary endpoint of the study was the major pathological response (MPR) rate. Secondary endpoints included the pathological complete response (pCR) rate, objective response rate (ORR), event-free survival (EFS), overall survival (OS), and safety. Results: Between February 2023 and June 2024, a total of 30 patients were enrolled. The median age was 64 years (range: 43-77 years), with 25 males (83.3%). Twenty-eight patients (93.3%) had squamous cell carcinoma, while 2 patients (6.7%) had adenocarcinoma. In terms of disease stage, 12 patients (40%) were at stage II, and 18 patients (60%) were at stage III. For treatment, 23 patients (76.7%) received three cycles of neoadjuvant immunotherapy, and 7 patients (23.3%) received four cycles. The objective response rate (ORR) was 53.3% and surgical resection was performed in 27 patients (90%), with a complete (R0) resection rate of 96.3% (26/27). A major pathological response (MPR) was observed in 53.3% (16/30) of patients, and the pathological complete response (pCR) rate was 33.3%(10/30). With a median follow-up of 12.1 months, the median event-free survival (EFS) and overall survival (OS) data were not yet mature. In the intention-to-treat (ITT) population, the 1-year EFS rate and OS rate were 92.3% and 96.7%, respectively. During the neoadjuvant phase, the incidence of treatment-related adverse events (TRAEs) of any grade was 70%, with grade 3-4 adverse reactions occurring in 13% of patients. Conclusions: Perioperative tislelizumab achieved notable major pathological response (MPR) and pathological complete response (pCR) rates, while also demonstrating feasible surgical resection and manageable toxicity in patients with stage II-IIIB non-small cell lung cancer (NSCLC). The current data align with the initial findings and underscore the need for continued follow-up to further validate these outcomes. Clinical trial information: ChiCTR2300068140 .