Tazemetostat (Tazemetostat), developed by Epizyme, a subsidiary of Ipsen, is the first-in-class EZH2 methyltransferase inhibitor. It received FDA accelerated approval in January and June 2020 for treating advanced epithelioid sarcoma and certain relapsed/refractory FL (R/R FL) patients, respectively. By inhibiting EZH2, Tazemetostat prevents H3K27 methylation, restores tumor suppressor gene expression, and allows B cells to continue differentiation or undergo apoptosis, thereby controlling tumor growth.
A global Phase 1b/3 confirmatory study—multicenter, randomized, double-blind, active-controlled, and biomarker-enriched—assessed the safety and efficacy of Tazemetostat in combination with rituximab and lenalidomide (R² regimen) for R/R FL patients who had received at least one prior line of therapy. Phase 1b results showed promising outcomes, with an overall response rate (ORR) of 90.9%. In the cohort receiving the Phase 3 recommended dose, the estimated 18-month progression-free survival (PFS) and duration of response (DoR) rates were 94.4% and 100%, respectively, with no dose-limiting toxicities observed.
Follicular lymphoma (FL) is a type of non-Hodgkin lymphoma (NHL) that originates from germinal center B cells and retains partial follicular structures. It accounts for approximately 8%–23% of B-cell NHL cases. FL is an indolent and largely incurable disease, characterized by significant biological and clinical heterogeneity and a wide range of treatment options.
According to the China’s National Medical Products Administration (NMPA), on March 21, Tazemetostat was approved for the treatment of relapsed or refractory FL in EZH2 mutation-positive patients who have received at least two prior systemic therapies.
