Bendamustine in heavily pre-treated patients with relapsed or refractory multiple myeloma.

PURPOSE: Treatment options for patients with relapsed and refractory multiple myeloma have improved since the introduction of immune-modulating agents such as lenalidomide and thalidomide. However, almost all patients relapse and suffer from an increasing amount of adverse events due to multiple lines of therapy that eventually lead to a reduced quality of life.

METHODS: In this bicentric retrospective analysis, 58 patients who had been treated with either bendamustine monotherapy (62 % of the patients) or combined steroid therapy were included. Further inclusion criteria were at least relapsed disease. Patients had previously been treated with a mean of four lines of therapy (range 1-10). They received a median of three cycles of treatment. Dosage varied from 60 to 300 mg/m(2) (median 120 mg/m(2)) and was administered intravenously on day 1 and 2 of a 28-day cycle.

RESULTS: Observed toxicity was mild and most commonly led to hematological side effects such as thrombopenia and anemia. Response rates were as follows: no complete response, 20 % partial response, 39 % minimal response, 27 % stable disease and 14 % progressive disease. Median overall survival (OS) was 17 months. Median event-free survival was 7 months. Patients who had not received a concomitant steroid had a median OS of 17 months compared to 13 months median OS for patients who had received a concomitant steroid.

CONCLUSION: Bendamustine monotherapy is an effective treatment option for heavily pre-treated myeloma patients due to its favorable response rate and mild toxicity.