Purpose: This multicenter, phase II study examined the efficacy and safety of bendamustine plus rituximab in patients with relapsed or progressive marginal zone lymphoma (MZL).
Materials and methods: Patients received six cycles of bendamustine 90 mg/m2 intravenously on days 2 and 3, rituximab 375 mg/m2 intravenously in cycle 1, and 1,400 mg subcutaneously in cycles 2-8 on day 1 every 4 weeks. Bendamustine dose reduction to 60 mg/m2 (level -1) and 40 mg/m2 (level -2) was allowed based on prespecified toxicity criteria. The primary endpoint was overall response rate (ORR) and the secondary endpoints included progression-free survival (PFS), overall survival (OS), and safety.
Results: Among the 26 evaluable patients, 81.8% achieved an ORR, while 40.7% had a complete response. The median PFS was 46.06 months, and the estimated 3-year OS rate was 92.3%. Hematological toxicities, primarily neutropenia (grade 3/4, 48.1%), were the most common adverse events, resulting in both reduction and interruption of bendamustine doses, accounting for 18 (75%) of 24 dose-reduced cycles and 7 (41%) of 17 missed cycles, respectively. Nonhematologic toxicities were generally mild, with nausea and fatigue identified as the most frequently reported toxicities. The mean relative dose intensities were 76.9% (range, 31.5-100) for bendamustine and 91.3% (range, 72.7-100) for rituximab.
Conclusion: Bendamustine plus rituximab is a highly effective and tolerable treatment for patients with relapsed or progressive MZL, providing durable disease control.
Keywords: Bendamustine hydrochloride; Marginal zone lymphoma; Rituximab.