Monoclonal antibody treatment and agents with known prolonged half-lives: At least three half-lives must have elapsed prior to enrollment.\r\n* Note: a list of the half-lives of commonly used monoclonal antibodies is available on the Pediatric Brain Tumor Consortium (PBTC) webpage under Generic Forms and Templates Monoclonal antibodies: At least 7 days or 3 half-lives, whichever is longer, must have elapsed since prior treatment with a monoclonal antibody. Prior chemotherapy: Patients should be at least 30 days from last chemotherapy dose prior to start of CED infusion, with exception of antibody half-lives. For antibody therapies, at least 3 half-lives of the antibody after last dose of monoclonal antibody should have passed prior to CED infusion At least 3 half-lives must have elapsed since prior therapy that included a monoclonal antibody with the exception of blinatumomab; patients must have been off blinatumomab infusion for at least 7 days and all drug related toxicity must have resolved to grade 2 or lower as outlined in the inclusion/exclusion criteria Prior monoclonal antibody therapy within 5 half-lives or 7 days prior to apheresis, whichever is greater Monoclonal antibody treatment: at least three half-lives must have elapsed prior to registration Monoclonal antibody treatment and agents with known prolonged half-lives: < 3 halflives have elapsed or ? 28 days prior to screening, whichever is longer. Must not have received monoclonal antibodies within at least 3 half-lives of the antibody after its last dose. Patients should be at least 30 days from last chemotherapy dose prior to start of CED infusion, with exception of antibody half-lives; for antibody therapies, at least 3 half-lives of the antibody after last dose of monoclonal antibody should have passed prior to CED infusion Monoclonal antibody within 5 half-lives of the antibody prior to initiating protocol therapy At least three (3) half-lives of the antibody must have elapsed since the last dose of a monoclonal antibody At least 3 half-lives must have elapsed since prior therapy that included a monoclonal antibody Monoclonal antibody(ies) (At least 3 half-lives since the last dose of any monoclonal antibody prior to first dose of tazemetostat) At least 3 half-lives must have elapsed after treatment with a monoclonal antibody and enrollment on this study At least 3 half-lives of the antibody after the last dose of a monoclonal antibody. Monoclonal antibodies: at least 3 half-lives of the antibody after the last dose of a monoclonal antibody; specifically for bevacizumab 36 days after the last dose Monoclonal antibodies: At least 7 days or 3 half-lives, whichever is longer, must have elapsed since prior treatment with a monoclonal antibody. At least 3 half-lives should have elapsed since therapy with a monoclonal antibody Monoclonal antibody treatment and agents with known prolonged half-lives: at least three half-lives must have elapsed prior to enrollment Antibodies: 3 half-lives must have elapsed from infusion of last dose of antibody (including checkpoint inhibitors), and toxicity related to prior antibody therapy must be recovered to Grade ?1. Monoclonal antibodies: at least 3 half-lives of the antibody after the last dose of a monoclonal antibody At least 7 days or 3 half-lives, whichever is longer, must have elapsed since prior treatment with a monoclonal antibody Monoclonal antibody (ies) (At least 3 half-lives since the last dose of any monoclonal antibody prior to first dose of tazemetostat) Has received prior treatment with a monoclonal antibody within 5 half-lives of Study Day 1 Received prior treatment (for any reason)with a monoclonal antibody within 5 half-lives of initiating study treatment Has received prior treatment with a monoclonal antibody within 5 half-lives of Study Day 1 Monoclonal antibody; at least three half-lives since the last dose Monoclonal antibody treatment and agents with known prolonged half-lives: at least three half-lives must have elapsed prior to enrollment Subjects must have completed at least 3 half-life periods from the last dose of monoclonal antibody prior to registration \r\n* Note: a list of half-lives of commonly used monoclonal antibodies is available on the Pediatric Brain Tumor Consortium (PBTC) website under Generic Forms and Templates At least 3 antibody half?lives must have elapsed since the last dose of monoclonal antibody (e.g., 66 days for rituximab and 69 days for epratuzumab) before subjects may initiate study treatment. Monoclonal antibodies: ?21 days or 3 half-lives (whichever is shorter) of the antibody must have elapsed after the last dose of a monoclonal antibody (including checkpoint inhibitors). Toxicity related to prior antibody therapy must be recovered to Grade ?1 At least 3 half-lives of the antibody must have elapsed after the last dose of monoclonal antibody. (i.e. gemtuzumab = 36 days) Monoclonal antibodies: At least 3 half-lives of the antibody must have elapsed after the last dose of monoclonal antibody. (ie. Rituximab=66 days, Epratuzumab=69 days) RECURRENT/ PROGRESSIVE DIPG (STRATUM 1): Monoclonal antibody treatment and agents with known prolonged half-lives: at least three half-lives must have elapsed prior to enrollment\r\n* Note: A list of the half-lives of commonly used monoclonal antibodies is available on the Pediatric Brain Tumor Consortium (PBTC) webpage under Generic Forms and Templates At least 7 days or 3 half-lives, whichever is longer, must have elapsed since prior treatment with a monoclonal antibody Monoclonal antibodies: Last dose of any monoclonal antibodies must have received at least 7 days or 3 half-lives, whichever is longer, prior to the start date for protocol therapy. Please refer to table posted at www.nant.org for definition of half-lives for specific monoclonal antibodies. Therapeutic monoclonal antibody use within the longer of 6 weeks or 5 plasma half-lives Monoclonal antibody: ?3 half-lives of antibody since last admin.