Feasibility and pharmacokinetic study of bendamustine hydrochloride in combination with rituximab in relapsed or refractory aggressive B cell non‐Hodgkin’s lymphoma

摘要

AbstractAlthough bendamustine plus rituximab has demonstrated efficacy in indolent B cell non-Hodgkin’s lymphoma (B-NHL), data for this combination in aggressive B-NHL are extremely limited. The present dose-escalation study evaluated the safety, efficacy, and pharmacokinetics of bendamustine hydrochloride in combination with rituximab in patients with relapsed/refractory, CD20-positive, aggressive B-NHL. Patients received rituximab 375 mg/m2, i.v., on Day 1 and bendamustine at either 90 (Cohort 1) or 120 mg/m2 (Cohort 2), i.v., on Days 2 and 3 of a 21-day cycle. The primary endpoint was the proportion of patients experiencing dose-limiting toxicity (DLT). Secondary endpoints were adverse events (AE), the overall response rate (ORR), and pharmacokinetic parameters. Nine patients received rituximab plus bendamustine: three in Cohort 1 and six in Cohort 2. Histologies included diffuse large B cell lymphoma (n = 5), mantle cell lymphoma (n = 2), and transformed lymphoma (n = 2). No DLT was observed at either dose level. Grade 3/4 hematologic AE included lymphocytopenia, leukocytopenia, and neutropenia (n = 9 each; 100%), and thrombocytopenia (n = 2; 22%). No Grade 3/4 gastrointestinal AE were reported. The ORR was 33% (one partial response) in Cohort 1 and 100% (five complete and one partial response) in Cohort 2. The maximum drug concentration and area under the blood concentration–time curve for bendamustine increased dose dependently, with time to maximum blood concentration = 1.0 h in both cohorts; these pharmacokinetic data were similar to those reported previously for single-agent bendamustine in patients with indolent B-NHL. In conclusion, bendamustine 120 mg/m2 plus rituximab 375 mg/m2 was feasible and generally well tolerated, with promising efficacy in relapsed or refractory aggressive B-NHL. (Cancer Sci 2011; 102: 1687–1692)