Randomized phase II study of mogamulizumab (KW-0761) plus VCAP-AMP-VECP (mLSG15) versus mLSG15 alone for newly diagnosed aggressive adult T-cell leukemia-lymphoma (ATL).

8506 Background: Mogamulizumab (Moga), a defucosylated humanized anti-CCR4 antibody, was approved for the treatment of relapsed/refractory ATL in Japan in 2012. This multicenter, randomized, phase II trial was conducted to examine the efficacy of the combination of Moga with standard chemotherapy for untreated aggressive ATL. Methods: Previously untreated patients (pts) with CCR4-positive ATL were randomly assigned to receive mLSG15 plus Moga (arm A) or mLSG15 alone (arm B). The primary endpoint was CR rate (%CR), and secondary endpoints included ORR, PFS, OS and safety. Pts received 4 courses of mLSG15 regimen, with or without a total of 8 doses of Moga (1.0 mg/kg) once every 2 weeks. The planned sample size, 22 pts per arm, provided a probability of 80% that %CR in arm A would have larger %CR when true %CR for arm A is 15% better than that for arm B. Results: Of 54 pts randomized, 53 were treated (arm A: 29; arm B: 24). Male/female ratio was 53/47%, median age was 63 (37-81), and subtype was acute/lymph...