In addition, tazemetostat has been tested in solid tumors with notable preclinical activity in pediatric malignant rhabdoid tumors, which harbor inactivating biallelic mutations in the SWI/SNF subunit SMARCB1 as well as SMARCB1-deificent synovial sarcoma (157, 162). This evidence concerns the gene SMARCB1 and synovial sarcoma.