Lenalidomide plus dexamethasone vs. lenalidomide plus melphalan and prednisone: a retrospective study in newly diagnosed elderly myeloma.

BACKGROUND: The goal of this retrospective study was to compare the efficacy and toxicity of lenalidomide-dexamethasone (len/dex) vs. melphalan-prednisone-lenalidomide (MPR) as upfront therapy for newly diagnosed elderly patients with myeloma. METHODS: Data from 51 patients enrolled in an Italian phase I/II trial and treated with MPR were analyzed and compared with data from 38 patients, seen at the Mayo Clinic, treated with len/dex and enrolled in phase II/III trials. RESULTS: On intention-to-treat analysis, time to progression (median: 24.7 vs. 27.5 months in MPR and len/dex groups, respectively, P = 0.903), progression-free survival (median: 24.7 vs. 27.5 months in MPR and len/dex groups, respectively, P = 0.926), and overall survival (2-yr overall survival: 86.2% in MPR vs. 89.1% in len/dex, P = 0.730) were not significantly different between the two groups. Results were confirmed when the analysis was restricted to MPR and len/dex matched pair mates. Hematologic grade 3-4 toxicities were more common with MPR (neutropenia: 66.7% vs. 21.1%, P < 0.001; thrombocytopenia: 31.4% vs. 2.6%, P < 0.001). Grade 3-4 gastrointestinal events (13.2% vs. 3.9%, P = 0.132), thrombotic events (13.2% vs. 5.9%, P = 0.279), and fatigue (10.5% vs. 3.9%, P = 0.395) were more common with len/dex. CONCLUSIONS: Results show that both MPR and len/dex are efficacious regimens for elderly patients with myeloma. Randomized trials are needed to confirm these results.