Kelly Valla, PharmD, BCOP, on Secondary Malignancies With Tazemetostat for Follicular Lymphoma

For the latest installment of the “Product Profile”, ONCOLOGY® spoke with Kelly Valla, PharmD, BCOP, about tazemetostat (Tazverik) as therapy for adult patients with relapsed or refractory follicular lymphoma harboring EZH2 mutation as detected by an FDA-approved test following at least 2 prior systemic therapies and for those who have no satisfactory alternative treatment options for their disease. Here, she discusses how the FDA halted a clinical trial because of the finding of T-cell lymphoblastic leukemia (T-LBL) in a pediatric patient receiving tazemetostat.

Transcript:

In early phases of investigation of tazemetostat, the FDA did halt, or pause, investigation of this agent due to a case of T-cell lymphoblastic lymphoma [T-LBL] in a pediatric patient. Secondary malignancies are of concern, [but] they did lift the halt. [The label of tazemetostat] has a note that it can cause secondary malignancies, including T-LBL and T-cell acute lymphoblastic leukemia, as well as myelodysplastic syndrome [MDS], and acute myeloid leukemia [AML].

In younger patients, we’re more concerned about those T-cell malignancies due to the active thymus. In adults, these really haven’t been seen to date, but cases of MDS and AML have been, although at very low rates. A few questions still need to be answered regarding whether or not tazemetostat is the sole contributor to the secondary malignancy or if prior treatment history was at play at all. Also, there may be a link [between] a longer duration of treatment with tazemetostat and the risk of secondary malignancies. Needless to say, the loss of function of EZH2 [due to] long-term inhibition can be pathogenic for MDS or myeloproliferative neoplasms.

Reference:

Epizyme announces the U.S. Food and Drug Administration lifts partial clinical hold on tazemetostat clinical program. News release. Epizyme. September 24, 2018. Accessed May 20, 2021. https://bit.ly/3oAwnpZ