Bendamustine and prednisone in combination with bortezomib (BPV) in the treatment of patients with relapsed or refractory multiple myeloma and light chain-induced renal failure.

Introduction: Serious renal failure represents a severe complication of multiple myeloma (MM), with an estimated 25-50 % of patients being affected. Both bortezomib and bendamustine have been identified as quickly acting, effective and well-tolerated drugs and might therefore constitute an adequate combination regimen for patients presenting with light chain-induced renal failure.

Methods: Between March 2005 and March 2013, 36 patients with relapsed/refractory MM and light chain-induced renal failure (creatinine clearance <60 ml/min) were treated with bendamustine 60 mg/m(2) on days 1 and 2, bortezomib 1.3 mg/m(2) on days 1, 4, 8 and 11 and prednisone 100 mg on days 1, 2, 4, 8 and 11 (BPV). Patients were divided according to severity of renal impairment into group A (n = 20) with moderate or severe renal dysfunction (eGFR 15-59 ml/min) and group B (n = 16) with renal failure/dialysis (eGFR <15 ml/min).

Results: Twenty-four patients (67 %) responded with three CR, three nCR, six VGPR and 12 PR. Six patients had minor response, two stable and four progressive disease. With a median follow-up period of 22 months, median progression-free survival (PFS) and overall survival (OS) for patients of group A were 10 and 25 months, respectively. This outcome was significantly better compared to patients of group B with a median PFS and OS of 3 and 7 months, respectively. Eleven patients showed a CRrenal, five a PRrenal and 15 a MRrenal. These results indicate that this BPV combination is feasible, effective and well tolerated in patients with relapsed/refractory MM and light chain-induced renal failure.