Perioperative tislelizumab plus neoadjuvant chemotherapy for patients with resectable non-small-cell lung cancer: final analysis of the randomized RATIONALE-315 trial.

[BACKGROUND] Perioperative immunotherapy, particularly anti-programmed cell death protein 1 therapy, combined with neoadjuvant chemotherapy has emerged as one of the standard-of-care options for resectable non-small-cell lung cancer (NSCLC). We report the final analysis of RATIONALE-315, a randomized, double-blind, phase III trial evaluating the efficacy and safety of perioperative tislelizumab plus neoadjuvant chemotherapy versus neoadjuvant chemotherapy alone in patients with resectable, stage II-IIIA NSCLC.

[PATIENTS AND METHODS] Adult patients in China were randomized (1 : 1) to receive either perioperative tislelizumab or placebo in combination with neoadjuvant chemotherapy. The dual primary endpoints were event-free survival (EFS) and major pathological response, assessed by blinded independent central review. The secondary endpoints included pathological complete response, overall survival (OS), disease-free survival, and safety.

[RESULTS] In total, 453 patients were randomized (226 to tislelizumab and 227 to placebo). At the final analysis (median study follow-up of 38.5 months), patients in the tislelizumab group experienced statistically significantly improved OS versus those in the placebo group {hazard ratio (HR) 0.65 [95% confidence interval (CI) 0.45-0.93]; P = 0.009}. The median OS was not reached in either group. The 36-month OS rate was 79.3% in the tislelizumab group versus 69.3% in the placebo group. The median EFS was not reached in the tislelizumab group versus 30.6 months in the placebo group [HR 0.58 (95% CI 0.43-0.79)]. Survival benefits were generally consistent across subgroups. The safety profile of tislelizumab plus chemotherapy was tolerable and consistent with known profiles of the individual therapies.

[CONCLUSIONS] Neoadjuvant tislelizumab plus chemotherapy and adjuvant tislelizumab demonstrated a statistically significant, clinically meaningful OS benefit and sustained, clinically meaningful EFS improvement compared with neoadjuvant chemotherapy, with a tolerable safety profile in patients with resectable stage II-IIIA NSCLC. These results support the use of this regimen in this patient population.

[CLINICAL TRIAL NUMBER] NCT04379635.