Dr. Riedell on the Clinical Utility of EZH2 Mutation Testing in Relapsed/Refractory FL

Peter Riedell, MD, assistant professor of Medicine, Section of Hematology and Oncology, The University of Chicago Department of medicine, discusses the clinical utility of EZH2 mutation testing when navigating treatment options for patients with relapsed/refractory follicular lymphoma (FL).

The EZH2 inhibitor tazemetostat (Tazverik) was approved by the FDA in 2020 for patients with relapsed/refractory EZH2-positive FL who have received at least 2 prior systemic therapies or who have relapsed/refractory disease with no other available satisfactory treatment options. Additionally, an associated EZH2 Mutation Test was concurrently approved by the FDA as a companion diagnostic for this population.

EZH2 mutation testing can help guide treatment decisions and optimize the selection of appropriate therapeutic interventions, Riedell begins. During treatment selection, this diagnostic tool’s predictive value may provide valuable insights into patient responses to tazemetostat in clinical practice, he expands.

Next-generation sequencing (NGS) is typically employed to identify EZH2mutations, Riedell continues. However, it is crucial to note that EZH2 mutations are relatively rare, he states. Ridell explains that approximately 20% of patients harbor these mutations, though the percentage may be lower outside of a clinical trial setting. Additionally, current research indicates that tazemetostat demonstrates efficacy in patients with both EZH2 wild-type and EZH2-mutant disease, Riedell notes, although tazemetostat may provide more benefit to those expressing EZH2 mutations. Consequently, the decision to initiate tazemetostat treatment is not solely determined by the presence or absence of this mutation, Riedell emphasizes.

Ultimately, this personalized approach can ensure that patients receive the most suitable treatment options, thereby improving their chances of a favorable response to therapy, Riedell concludes.