Bendamustine and rituximab (BR) are effective in the treatment of relapsed or refractory indolent and mantle-cell lymphomas: Long-term follow-up of a phase II study

Abstract

8034 Bendamustine combines a purine-like benzimidazol and bifunctionally alkylating nitrogen mustard group. The aim of this multicenter- study was to evaluate the progression-free survival (PFS), response rate and toxicity of BR in patients with mantle-cell or low-grade lymphomas in 1st to 3rd relapse or refractory to previous treatment. A median of 4 courses per patient were administered to 63 pts. Bendamustine was given at a dose of 90 mg/m 2 on day 1 and 2 combined with 375 mg/m 2 Rituximab on day 1 for a max. of 4 cycles every 4 weeks. Histologies: 24 follicular, 16 mantle cell, 17 lymphoplasmacytoid, 6 marginal zone lymphoma. 57 of 63 pts responded to BR corresponding to an overall response rate of 90% with a CR-rate of 60%. In mantle cell lymphomas BR showed a considerable activity achieving a response rate of 75% with a CR-rate of 50%. In an updated analysis the median time of PFS was 30 months and the median duration of overall survival has not yet been reached. With a median follow-up period of 3 years two secondary neoplasms have been observed (bronchial carcinoma). No MDS was observed to date. These results demonstrate that the combination of Bendamustine and Rituximab is a highly active regimen in the treatment of low-grade lymphomas and mantle cell lymphomas. Based upon these encouraging results the Studiengruppe indolente Lymphome (StiL) initiated two Phase III trials that compare BR to established chemo-immunotherapy regimens: BR vs R-CHOP in untreated pts, and BR vs Fludarabine- R in relapsed pts. These studies should provide considerable guidance for the appropriate role of Bendamustine in the treatment of low-grade and mantle cell lymphomas. No significant financial relationships to disclose.