Tazemetostat as treatment for patients with relapsed or refractory follicular lymphoma

This study aimed to investigate if tazemetostat (Tazverik) was a safe and effective treatment in patients with relapsed/refractory follicular lymphoma (FL). 

This study concluded that tazemetostat provided durable responses and was well tolerated in these patients.  

Tazemetostat is a drug that works by targeting the mutated (abnormal) EZH2 gene. This leads to slow down tumor growth. It is known as an EZH2 inhibitor. Mutations of EZH2 are present in 20% of patients with FL. The safety and effectiveness of tazemetostat in patients with relapsed or refractory FL remain under investigation. 

This study involved 99 patients with relapsed/refractory follicular lymphoma (FL). Patients were grouped based on EZH2 status: mutated (EZH2mut) or non-mutated (EZH2-NM). All patients were treated with 800 mg of tazemetostat twice daily in 28-day cycles. Patients were followed-up for an average of 22 months (EZH2mut group) and 35.9 months (EZH2-NM group).

Overall, 69% of the EZH2mut group responded to treatment compared to 35% in the EZH2-NM group. 13% of the EZH2mut group had a complete response (disappearance of all signs of cancer) compared to 4% in the EZH2-NM group. The average duration of response to treatment was 10.9 months for the EZH2mut group compared to 13 months for the EZH2-NM group.  

The average progression-free survival (PFS) was 13.8 months for the EZH2mut group compared to 11.1 months for the EZH2-NM group.  

Overall, 81% of patients experienced at least one side effect due to treatment. Serious side effects occurred in 27% of patients. The most common serious side effects were low platelet levels (3%), low levels of neutrophils (white blood cells that fight off infections; 3%), and anemia (2%). 

This study concluded that tazemetostat provided durable responses and was well tolerated in patients with relapsed/refractory FL who were heavily pretreated. 

This study had a rather short follow up period. Also, there was no comparison group. Further studies are needed. The study was funded by Epizyme, the manufacturer of tazemetostat.