Bendamustine and bortezomib have shown high activity boch in first-line regimens and pre-treated patients. The novel mechanism of action of the proteasome inhibitor and the non-cross resistance of bendamustine to other alkylating agents established in the first-line treatment of multiple myeloma seem to recommend a combination of the two drugs for salvage therapy (second-line regimen). Finally, the promising response data in a series of relapsing MM patients treated with bendamustine, bortezomib and prednisone support this assumption, as well as the feasibility and tolerability of the combination.