Tazemetostat, sold under the brand name Tazverik, is a medication used for the treatment of adults and adolescents aged 16 years and older with metastatic (when cancer cells spread to other parts of the body) or locally advanced (when cancer has grown outside the organ it started in, but has not yet spread to distant parts of the body) epithelioid sarcoma not eligible for complete resection (surgically removing all of a tissue, structure, or organ).

[1] Most cases of epithelioid sarcoma begin in the soft tissue under the skin of an extremity, though it can start in other areas of the body.

[1] According to the NCI Drug Dictionary, "tazemetostat is an orally available, small molecule selective and S-adenosyl methionine (SAM) competitive inhibitor of histone methyl transferase EZH2, with potential antineoplastic activity.

[4] The U.S. Food and Drug Administration (FDA) approved tazemetostat in January 2020,[1] based on the results of a clinical trial (NCT02601950) enrolling 62 subjects with metastatic or locally advanced epithelioid sarcoma.

[1] The trial measured how many subjects experienced complete or partial shrinkage (by a certain amount) of their tumors during treatment (overall response rate).