Update Regarding Tazemetostat Clinical Program
On April 23, Epizyme, Inc, announced that U.S.-based enrollment of new patients into tazemetostat clinical trials is temporarily on hold. Following a safety report of a pediatric patient who developed a secondary lymphoma, the U.S. Food and Drug Administration (FDA) issued a partial clinical hold affecting new enrollment of patients with genetically defined solid tumors and hematologic malignancies, while the company updates the informed consent, investigator’s brochure, and study protocols. Patients on study who have not experienced disease progression may continue to receive tazemetostat. Epizyme has begun developing the modifications to address the partial clinical hold, and will need to confirm alignment with the FDA in order to resume U.S. enrollment.
The partial clinical hold was initiated following a safety report submitted by Epizyme to the FDA and other regulatory authorities regarding a patient with advanced poorly differentiated chordoma in the company’s phase I pediatric study who developed a secondary T-cell lymphoma. Doses explored in this study are higher than those in the company’s phase II adult studies, an approach not uncommon to drug development in aggressive, difficult-to-treat pediatric cancers. At the time of the safety report, the patient had been on study for approximately 15 months and had achieved a confirmed partial response. This patient has now discontinued tazemetostat and is being treated for T-cell lymphoma.
T-cell lymphoma has been identified as a potential adverse event in tazemetostat study protocols and is included in the investigator’s brochure and the informed consent. More than 750 patients have been treated with tazemetostat to date, and this is the only case of secondary lymphoma that has been observed across the tazemetostat clinical program.
“Patient safety is of the utmost importance to Epizyme. We are working expeditiously with clinical trial investigators and regulatory authorities to initiate the appropriate steps to resume enrollment,” said Robert Bazemore, President and Chief Executive Officer of Epizyme. “Epizyme…has been very encouraged by the clinical responses and tolerability of tazemetostat observed in pediatric and adult patients with hematological malignancies and solid tumors enrolled in our trials. We remain encouraged by the potential of tazemetostat to address the unmet needs of many patients living with cancer.”
About the Tazemetostat Clinical Trial Program
Tazemetostat, a first-in-class EZH2 inhibitor, is currently being studied as a monotherapy in ongoing phase I and II programs in certain molecularly defined solid tumors, including epithelioid sarcoma and other INI1-negative tumors; both follicular lymphoma and diffuse large B-cell lymphoma (DLBCL) forms of non-Hodgkin lymphoma; mesothelioma; and combination studies in DLBCL and non–small cell lung cancer.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.