Epizyme places a Hold on Tazemetostat Clinical Program enrollment
Epizyme 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 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 1 pediatric study who developed a secondary T-cell lymphoma. Doses explored in this study are higher than those in the company's Phase 2 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. Secondary malignancies are known to be potential adverse events associated with many cancer therapies, including chemotherapy and radiation treatment. 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.