BeiGene has reported the Phase III RATIONALE 309 trial of its tislelizumab (BGB-A317), along with chemotherapy for treating recurrent or metastatic nasopharyngeal cancer (NPC) patients, met the primary goal.

A humanised immunoglobulin G4 anti-programmed cell death protein 1 (anti-PD-1) monoclonal antibody, tislelizumab can potentially lower binding to Fc gamma receptors (FcγR) on macrophages.

The randomised, double-blind, placebo-controlled Phase III RATIONALE 309 trial is comparing the efficacy and safety of tislelizumab plus gemcitabine and cisplatin to placebo plus gemcitabine and cisplatin as first-line therapy for recurrent or metastatic NPC patients.

The trial enrolled 263 participants in Asia. Its primary endpoint is progression-free survival (PFS).

Overall survival, objective response rate and duration of response and investigator-evaluated PFS are some of the secondary endpoints.

The interim analysis data showed that the trial met its primary endpoint, with tislelizumab plus chemotherapy providing a statistically significant improvement in PFS in the intention-to-treat population versus the placebo arm.

The antibody’s safety profile was in line with its already known risks and no new safety signals were detected in this trial when added to chemotherapy.

BeiGene Immuno-Oncology chief medical officer Yong Ben said: “We are excited to see a clinically meaningful improvement in progression-free survival in our Phase III trial for tislelizumab plus chemotherapy in patients with NPC.

“This is our fifth positive Phase III readout for tislelizumab, which we are developing broadly as a potentially differentiated anti-PD-1 antibody.”

The company intends to share the latest data with health authorities.

Tislelizumab has market authorisation from the China National Medical Products Administration (NMPA) for advanced squamous non-small cell lung cancer (NSCLC), classical Hodgkin’s lymphoma and locally advanced or metastatic urothelial carcinoma.

In January last year, BeiGene reported positive data from the Phase III clinical trial of tislelizumab in combination with chemotherapy as a first-line treatment for squamous NSCLC.

BeiGene and Novartis signed a partnership and licence agreement in January this year, through which Novartis gained rights to develop, produce and market tislelizumab in North America, Europe, and Japan.