A PHASE 2 TRIAL OF CHOP WITH ANTI‐CCR4 ANTIBODY MOGAMULIZUMAB FOR ELDERLY PATIENTS WITH CCR4‐POSITIVE ADULT T‐CELL LEUKEMIA/LYMPHOMA

Background: No standard of care for elderly patients with aggressive adult T-cell leukemia/lymphoma (ATL) has been established yet. We assessed the efficacy an anti-CCR4 antibody, mogamulizumab (Moga)combined biweekly cyclophosphamide (CPA), doxorubicin (DXR), vincristine (VCR), and prednisone (PSL) (Moga-CHOP-14) untreated ATL. Methods: In this phase 2 trial conducted at 21 centers in Japan, CCR4-positive ATL aged 66 years or older 56–65 who were not candidates allogeneic hematopoietic stem cell transplantation (allo-HSCT) received six cycles Moga-CHOP-14, followed by two Moga monotherapy. The primary endpoint was 1-year progression-free survival (PFS), defined as time from enrollment to progression/relapse death due any cause, whichever occurred first. Secondary endpoints complete response rate (CR), overall (ORR), (OS), event-free (EFS), incidence adverse events. necessary number calculated setting threshold 1-yearPFS 16% expected PFS 31% using exact method based on binomial distribution under conditions one-sided level significance 5% (α = 0.05) power 70% 43. Results: A total 50 enrolled October 2015, until September 2020. Among 48 evaluable patients, median age was74 (interquartile range [IQR], 70–78). subtypes included 31, 9, 8 acute, lymphoma, unfavorable chronic type, respectively. ATL-PI high, intermediate, low risk, With a follow-up 1.6years (IQR, 0.7–2.4), 36.2% (90% confidence interval (CI), 24.9–47.6), 0.7 (95% CI, 0.5–1.0).CR ORR noted 64.6% 49.5–77.8), 91.7%(95% 80.0–97.7), One-year OS 66.0% 50.6–77.6) 1.6 1.1–2.8). EFS 29.9% 17.6–43.2) 0.5 0.4–0.7). most frequent events grades 3/4, which >10% lymphocytopenia (97.9%), leukopenia (93.8%), neutropenia (89.6%), febrile (64.8%), anemia (58.3%), thrombocytopenia (45.8%), infection (27.1%), skin rash (20.8%), hyperglycemia (20.8%). Relative dose intensity (RDI) each drug: mean RDI 82.1%, CPA 71.7%, DXR 72.7%, VCR 72.0%, PSL 77.3%. Conclusions: This study demonstrated that Moga-CHOP-14 significantly improved ineligible allo-HSCT. is now considered preferred first-line treatment those patients. Clinical ID:jRCTs041180130. Encore Abstract—previously submitted ASCO 2023 research funded by: Kyowa Kirin Japan Agency Medical Research Development Keyword: combination therapies Conflicts interests pertinent abstract A. Utsunomiya Consultant advisory role: JIMRO, Otsuka Devices Honoraria: Bristol-Myers Squibb Meiji Seika Kaisha S. Kusumoto Chugai Pharma, Kirin, Daiichi Sankyo funding: M. Yoshimitsu Takeda Takeda, Sanofi, Novartis, K. Nosaka Seika, Janssen, Abbvie, Sankyo, Eisai, Rai Ono Pharmaceutical D. Nakamura Nippon Shinyaku, Ishitsuka Celgene, Pfizer, CSL Behring, Yakult Honsha, Pharmaceutical, Otsuka, Astellas Pharma Blood Products Organization, Taiho MSD, Sumitomo Dainippon Mochida