General Information

Tazverik (tazemetostat) blocks activity of the EZH2 methyltransferase, which may help keep the cancer cells from growing.

Tazverik is specifically indicated for the following:

• adults and pediatric patients aged 16 years and older with metastatic or locally advanced epithelioid sarcoma not eligible for complete resection
• adult patients with relapsed or refractory FL whose tumors are positive for an EZH2 mutation as detected by an FDA-approved test and who have received at least two prior systemic therapies
• adult patients with relapsed or refractory FL who have no satisfactory alternative treatment options

Tazverik is supplied as a tablet for oral administration. The recommended dose is 800 mg orally twice daily with or without food until disease progression or unacceptable toxicity. Swallow tablets whole. Do not take an additional dose if a dose is missed or vomiting occurs after Tazverik, but continue with the next scheduled dose.

Clinical Trials

Tazverik was granted accelerated approval for epithelioid sarcoma. Continued approval for this indication is contingent upon verification and description of clinical benefit in a confirmatory trial. 

The FDA approval of Tazverik for epithelioid sarcoma was based on the results of a clinical trial enrolling 62 patients with metastatic or locally advanced epithelioid sarcoma. During the clinical trial, patients received 800 milligrams (mg) of Tazverik twice a day until the disease progressed or the patient reached an unacceptable level of toxicity. Tumor response assessments were performed every eight weeks during the clinical trial. The trial measured how many patients experienced complete or partial shrinkage (by a certain amount) of their tumors during treatment (overall response rate). The overall response rate was 15%, with 1.6% of patients having a complete response and 13% having a partial response. Of the nine patients that had a response, six (67%) patients had a response lasting six months or longer.

Tazverik was granted accelerated approval for follicular lymphoma based on overall response rate and duration of response. Continued approval for these indications may be contingent upon verification and description of clinical benefit in a confirmatory trial(s).

The FDA approval of Tazverik for follicular lymphoma was based on an open-label, single-arm, multi-center Phase 2 clinical trial in patients with histologically confirmed FL whose disease had progressed following at least two prior systemic treatment regimens. Patients were enrolled into two cohorts: one cohort enrolled 45 patients with EZH2 activating mutations and a second cohort enrolled 54 patients with wild-type EZH2. All patients were treated with 800 mg of tazemetostat, administered orally twice a day. The major efficacy outcome measures were overall response rate (ORR) and duration of response (DOR). Among the 45 FL patients with an EZH2 activating mutation who received Tazverik and treated with at least 2 prior systemic therapies, the ORR was 69%, with 12% of patients achieving a complete response and 57% achieving a partial response. The median DOR was 10.9 months and ongoing. Among the 54 FL patients with wild-type EZH2 who received Tazverik and treated with at least 2 prior systemic therapies, the ORR was 34%, with 4% of patients achieving a complete response and 30% achieving a partial response. The median DOR was 13.0 months.

Side Effects

Adverse effects associated with the use of Tazverik may include, but are not limited to, the following:

• pain
• fatigue
• nausea
• decreased appetite
• vomiting
• constipation

Mechanism of Action

Tazverik (tazemetostat) is a potent, selective, and orally bioavailable small-molecule inhibitor of EZH2 enzymatic activity. EPZ-6438 induces apoptosis and differentiation specifically in SMARCB1-deleted MRT cells.

Additional Information

For additional information regarding Tazverik or epithelioid carcinoma, please visit the Tazverik web page.