FDA Grants Priority Review to Tazemetostat for Epithelioid Sarcoma

Epizyme, Inc is seeking approval from the FDA for tazemetostat for the treatment of epithelioid sarcoma not eligible for curative surgery, according to a press release.

The company announced that the agency granted Priority Review for the New Drug Application (NDA) and has set a Prescription Drug User Fee Act target action date of January 23, 2020.

Epithelioid sarcoma is an ultra-rare and aggressive soft tissue sarcoma with a median overall survival of less than 1 year in patients with metastatic disease, according to Epizyme. The disease most commonly affects individuals between 20 and 40 years of age.

The NDA submission is based on data from the epithelioid sarcoma cohort of the phase 2 study, which evaluated the safety and efficacy of tazemetostat, a first-in-class EZH2 inhibitor. The data were presented at the 2019 American Society of Clinical Oncology Annual Meeting.

The study enrolled 62 patients with epithelioid sarcoma, including 24 treatment-naïve patients and 38 relapsed and/or refractory patients. Patients were given 800 mg of tazemetostat orally twice per day.

Overall, the data showed that treatment with tazemetostat resulted in a 15% objective response rate and a 26% disease control rate (DCR). The median duration of response has not been yet been reached. Safety data observed in the study are consistent with the overall safety observed to date in more than 800 patients in the tazemetostat clinical program.

“This is a significant achievement in the development of this potentially first-in-class EZH2 inhibitor, and we look forward to working with FDA during the review,” Robert Bazemore, president and chief executive officer of Epizyme, said in a statement. “If approved, we believe tazemetostat could become an important new option in the treating physicians’ arsenal. We would like to extend our sincerest gratitude to those patents, families, and medical teams who have participated in our clinical studies and helped bring tazemetostat to this stage.”

Tazemetostat is also being studied for use in patients with follicular lymphoma, both with and without EZH2-activating mutations, as well as for diffuse large B-cell lymphoma.

To support full approval, Epizyme plans to initiate a confirmatory clinical trial comparing tazemetostat in combination with doxorubicin versus placebo plus doxorubicin in approximately 150 patients. The primary efficacy endpoint will be progression-free survival, with secondary endpoints including overall survival, DCR, overall response rate, and duration of response.

References

Epizyme Announces FDA Filing Acceptance of New Drug Application and Priority Review for Tazemetostat for the Treatment of Epithelioid Sarcoma [news release]. Epizyme. https://epizyme.gcs-web.com/news-releases/news-release-details/epizyme-announces-fda-filing-acceptance-new-drug-application-and. Accessed July 25, 2019.

Epizyme Reports Updated Data from Phase 2 Trial of Tazemetostat for Epithelioid Sarcoma at 2019 ASCO Annual Meeting [news release]. Epizyme. https://epizyme.gcs-web.com/news-releases/news-release-details/epizyme-reports-updated-data-phase-2-trial-tazemetostat. Accessed July 25, 2019.