Study of Tazemetostat as Single Agent in Solid Tumors or B-cell Lymphomas and in Combination With Prednisolone in DLBCL

This is a multicenter, open-label, Phase 1/2 study conducted in two parts: The Phase 1 part comprised dose escalation and expansion to establish the maximum tolerated dose (MTD) and/or the recommended Phase 2 dose (RP2D) when tazemetostat was given twice daily (BID) orally on a continuous basis. Additionally, in separate cohorts in Phase 1, the effect of food on the bioavailability of tazemetostat as well as the drug-drug interaction (DDI) potential of tazemetostat were evaluated. The Phase 2 part was initiated once the RP2D was established. Phase 2 enrolled subjects with relapsed/ refectory (R/R) DLBCL (Cohorts 1-3 and 6) and subjects with R/R FL (Cohorts 4 and 5) for the determination of efficacy and safety of tazemetostat monotherapy (Cohorts 1-5) and of tazemetostat in combination with prednisolone (Cohort 6) with placement determined by centrally confirmed histology, cell of origin (COO), and enhancer of zeste homologue 2 (EZH2) mutation status.