BeiGene's anti-PD-1 antibody tislelizumab is one step closer to winning BLA approval in the U.S. as a treatment for unresectable recurrent locally advanced or metastatic esophageal squamous cell carcinoma (ESCC) after prior systemic therapy, after the FDA accepted the application on Sep. 13.
Tislelizumab has not been approved anywhere else besides China, where it has been cleared for five indications.
The BLA was submitted jointly with Novartis, which acquired the rights to develop, manufacture, and commercialize tislelizumab in North America, Europe and Japan in January 2021.
The filing was based on results from RATIONALE 302, a randomized, open-label, multicenter global phase III trial to evaluate the efficacy and safety of tislelizumab compared to investigator’s choice chemotherapy as a second-line treatment for patients with advanced or metastatic ESCC.
The results were presented at ASCO 2021. Tislelizumab clinically and significantly improved overall survival (OS) versus investigator-chosen standard chemotherapy in the intent-to-treat population (median OS: 8.6 versus 6.3 months; HR 0.70, 95% CI 0.57-0.85, p=0.0001).
Treatment with tislelizumab was also associated with a higher overall response rate (20.3% versus 9.8%) and more durable response (median duration of response: 7.1 vs 4.0 months; HR 0.42, 95% CI 0.23-0.75) than investigator-chosen standard chemotherapy in the intent-to-treat population.
Besides BeiGene, other Chinese drugmakers, including Junshi Biosciences, Innovent Biologics and Akeso are also seeking approvals for their PD-1 drugs in the U.S.