Duvelisib is a novel dual inhibitor of phosphoinositide-3-kinase (PI3K)-δ and -γ. This single-arm, multicenter phase I study investigated its safety, pharmacokinetics, and preliminary efficacy in Japanese patients with relapsed or refractory lymphoma. Duvelisib was administered orally twice daily at 25 mg in 28-day cycles. Seven patients, comprising 4 with follicular lymphoma (FL), 2 with diffuse large B-cell lymphoma, and 1 with mantle cell lymphoma (MCL) were enrolled. No dose-limiting toxicity occurred in any patient. The most commonly experienced treatment-related adverse events of any grade were neutropenia and thrombocytopenia, occurring in 3 patients each (42.9%); followed by lymphopenia, diarrhea, enterocolitis, stomatitis, hepatic function abnormal, ALT increased, and AST increased, occurring in 2 patients each (28.6%). The most common grade ≥ 3 treatment-related adverse events were neutropenia, which occurred in 3 patients (42.9%), and thrombocytopenia, lymphopenia, and hepatic function abnormal, which occurred in 2 patients each (28.6%). One patient with FL achieved a complete response; the remaining 3 with FL and the 1 with MCL achieved a partial response. The overall response rate was 71.4% (5/7 patients). Duvelisib was well tolerated in Japanese patients with relapsed or refractory lymphoma. Safety and preliminary efficacy data support further development of duvelisib in Japanese patients.
All Science Journal Classification (ASJC) codes