Bendamustine, Low-dose dexamethasone, and lenalidomide (BdL) for the treatment of patients with relapsed/refractory multiple myeloma confirms very promising results in a phase I/II study

Lenalidomide and dexamethasone are an effective treatment for naïve and relapsed multiple myeloma (MM) patients. Bendamustine is a good option for B-cell malignancies showing only partial cross resistance with alkylating agents used in MM patients. Based on these considerations, we proposed a phase I/II study testing escalating doses of bendamustine and lenalidomide and fixed low doses of dexamethasone (BdL). Fifteen patients were enrolled in phase I study. Maximum tolerated dose was established at dose “level 0”: bendamustine 40 mg/m² days 1,2; lenalidomide 10 mg days 1–21; d 40 mg days 1,8,15,22 every 28-day cycle, for six cycles. We enrolled 23 patients in the phase II study. BdL combination showed mainly hematological toxicities, fever and infections. Overall response rate was 47%. After median follow up of 22 months, median PFS was 10 months. Two-years OS rate was 65%. BdL combination confirmed to be a promising treatment for patients with relapsed/refractory MM.