Japanese MHLW approves Ezharmia for relapsed or refractory adult T-cell leukemia/lymphoma

Ezharmia previously received Orphan Drug Designation (ODD) from the MHLW for this indication and is now the first dual inhibitor of EZH1 and EZH2 to be approved for treatment of ATL. A rare and aggressive hematologic malignancy that can manifest as either leukemia or lymphoma, ATL occurs with higher frequency in certain regions of Japan and is associated with a five-year overall survival rate of approximately 14%.

The approval of Ezharmia by the MHLW is based on results of an open-label, single-arm pivotal phase II study evaluating efficacy and safety in 25 patients with three aggressive subtypes of relapsed or refractory ATL in Japan. The study demonstrated an objective response rate (ORR) of 48% (95% CI: 27.8%-68.7%), as evaluated by an independent efficacy assessment committee. Complete responses (CR) were seen in 20% of patients (n=5) and partial responses (PR) in 28% of patients (n=7).

Ezharmia was generally well-tolerated in the phase II study. Drug-related treatment emergent adverse events occurred in 24 of 25 patients (96%) with the most common including platelet count decrease (80%), anemia (44%), alopecia (40%), dysgeusia (36%), lymphocyte count decrease (20%), neutrophil count decrease (20%) and white blood cell count decrease (20%).