The bridging study is a multicenter, open-label, Phase II study to evaluate the efficacy, safety and pharmacokinetics of tazemetostat for the treatment of patients with relapsed/refractory follicular lymphoma (“R/R FL”). The primary objective is to evaluate the objective response rate (“ORR”) of tazemetostat for the treatment of patients with R/R FL whose disease harbor EZH2¹ mutations (Cohort 1). The secondary objectives included duration of response (“DoR”), progression-free survival (PFS), and overall survival (OS) of tazemetostat for the treatment of R/R FL patients whose disease do or do not harbor EZH2 mutations (Cohort 2), as well as to evaluate the safety and pharmacokinetics. The lead principal investigator is Dr Junning Cao of Shanghai Fudan University Cancer Center. A total of 42 patients were enrolled. Additional details may be found at clinicaltrials.gov, using identifier NCT05467943.

Tazemetostat is a first-in-class methyltransferase inhibitor of EZH2 developed by Epizyme, Inc. (“Epizyme”), an Ipsen company. It is approved by the U.S. Food and Drug Administration (“FDA”) for the treatment of certain patients with advanced epithelioid sarcoma (“ES”) and certain patients with R/R FL under the FDA accelerated approval granted in January and June 2020, respectively. HUTCHMED entered into a strategic collaboration to research, develop, manufacture and commercialize tazemetostat in China, Hong Kong, Macau and Taiwan.

In May 2022, tazemetostat was approved by the Health Commission and Medical Products Administration of Hainan Province of China to be used in the Hainan Boao Lecheng International Medical Tourism Pilot Zone (“Hainan Pilot Zone”), under the Clinically Urgently Needed Imported Drugs scheme, for the treatment of certain patients with ES and FL consistent with the label as approved by the FDA.

In March 2023, tazemetostat was approved and launched in Macau. A market authorization application has been under review in Hong Kong since December 2022.

Tazemetostat was included in the Chinese Society of Clinical Oncology (CSCO) guidelines for ES in 2022 and for FL in 2023.