Therapeutic approach for relapsed/refractory multiple myeloma: the logic and practice.

The long-term outcome of multiple myeloma (MM) has been greatly improved by the advent of new agents such as proteasome inhibitors (PIs) and immunomodulatory drugs (IMiDs), despite the disease remaining mostly incurable. Treatment design is the critical determinant for the survival period and for the quality and way of life in patients with relapsed/refractory MM (RRMM). Recently, the choice of therapeutic options for RRMM has been expanded by the introduction of second generation PIs such as carfilzomib and ixazomib, and therapeutic monoclonal antibodies such as elotuzumab and daratumumab. In the choice of treatment strategies for RRMM, including stem cell transplantation, the decision should be based on an understanding of the characteristic clinical effects of each drug and the evaluation of the cytogenetic/molecular profile, myeloma-defining events, complications, and prior MM treatment history in individual patients.