BeiGene, Ltd. announced new data from RATIONALE 306, a global Phase 3 trial evaluating tislelizumab plus chemotherapy in adult patients with advanced or metastatic esophageal squamous cell carcinoma (ESCC) without prior systemic treatment for advanced disease. Study results presented as a late-breaking oral presentation at the 2022 European Society for Medical Oncology (ESMO) World Congress on Gastrointestinal Cancer (Abstract #LBA-1) showed a statistically significant and clinically meaningful improvement in overall survival (OS) for patients receiving tislelizumab in combination with chemotherapy with a median OS of 17.2 months [95% CI: 15.8,20.1] versus 10.6 months [95% CI: 9.3,12.1] for those receiving chemotherapy plus placebo. The combination of tislelizumab with chemotherapy reduced the risk of death by 34% (HR=0.66 [ 95% CI: 0.54,0.80, p<0.0001]) compared to chemotherapy plus placebo.

The EMA is also reviewing tislelizumab for advanced or metastatic non-small cell lung cancer (NSCLC) after prior chemotherapy, and in combination with chemotherapy for previously untreated advanced or metastatic NSCLC. In January 2021, BeiGene announced a collaboration with Novartis to accelerate the clinical development and marketing of tislelizumab in North America, Europe, and Japan. Tislelizumab is approved by the China National Medical Products Administration (NMPA) as a treatment for nine indications, including a recent approval for use in patients with locally advanced or metastatic ESCC who have disease progression or are intolerant to first-line standard chemotherapy.

Tislelizumab is not approved for use outside of China. About RATIONALE 306 RATIONALE 306 (NCT03783442) is a randomized, placebo-controlled, double-blind, global Phase 3 study to evaluate the efficacy and safety of tislelizumab in combination with chemotherapy as a first-line treatment in patients with advanced or metastatic ESCC. The primary endpoint of the trial is overall survival (OS).

Secondary endpoints include progression free survival, overall response rate, duration of response per RECIST v1.1, and OS in patients with PD-L1 score >=10%, as well as health-related quality of life measures and safety. The trial enrolled 649 patients at research centers across Asia-Pacific, Europe, and North America. Patients were randomized 1:1 to receive either tislelizumab plus chemotherapy or placebo plus chemotherapy.