Abstract
New classes of drugs including the proteasome inhibitors (PI) bortezomib and, more recently, carfilzomib and the immunomodulatory agent lenalidomide have shown improved outcomes for multiple myeloma (MM) patients during the past decade. However, most of the studies reporting outcomes for patients receiving these drugs have relied on older data sets derived from large institutions that included patients not receiving their treatment at those facilities and represented only those eligible for clinical trials or were from sites where treatment options were limited. We have analyzed data from 258 MM patients who have received treatment with at least one of three agents: bortezomib, carfilzomib, and lenalidomide in a single clinic specializing in MM with respect to their responses and other outcomes to treatment regimens including these agents. Response rates were similar between these three drugs when used for the first time and again during subsequent treatment regimens. As expected, the clinical benefit rates (CBRs) were better for patients receiving their first treatment when compared to their use in subsequent treatment regimens. The CBRs were similar during their 2nd, 3rd, and 4th treatments containing these agents. Many patients refractory to these agents showed responses to regimens containing these same drugs when used in different combinations. In addition, patients refractory to one PI often responded to the other PI. The results of this study demonstrate that novel agents can be used repeatedly in novel combinations with significant clinical benefit for patients with MM.