Bortezomib-Melphalan-Prednisone (VMP) Versus MP As Initial Treatment for Patients Older Than 75 Years with Newly Diagnosed Multiple Myeloma

Although bortezomib-melphalan-prednisone (VMP) therapy is a well-established standard treatment for patients with multiple myeloma (MM) who are ineligible for high-dose therapy, it is not clear whether very elderly patients should be treated with VMP, considering the toxicities. The purpose of this case-control study was to compare the efficacy of VMP versus melphalan-prednisone or cyclophosphamide-prednisone (MP/CP) as initial therapy for very elderly patients.

We retrospectively studied 202 patients aged 75 years or older with newly diagnosed multiple myeloma between March 2007 and February 2015. One-hundred twenty two patients received VMP and eighty patients received MP/CP regimen were enrolled from 13 institutions throughout Korea.

Patient characteristics were comparable in these two groups. Overall response rate was 69.7% in VMP patients and 47.5% in MP/CP patients (P=0.002). Complete response rate was 24.6% in VMP patients and 10% in MP/CP patients (P=0.005). After a median follow-up for survivors of 28.4 months, progression-free survival was significantly different between the two groups (median 21.0 vs. 11.9 months in VMP and MP/CP group, respectively, P=0.037). Overall survival was also significantly different between the two groups (median 34.6 vs. 27.8 months in VMP and MP/CP group, respectively, P= 0.023). Hematologic grade 3-4 toxicities were more common with VMP (anemia: 29.1% vs 15.3%, P=0.077; thrombocytopenia: 39.3% vs. 15.3%, P < 0.001). Grade 2-4 diarrhea (22.5% vs. 2.8%, P = 0.001), vomiting (13.7% vs. 1.4%, P = 0.011), and peripheral sensory neuropathy (35.3% vs. 4.2%, P <0.001) were also more common with VMP.

Despite the presence of age-related comorbidities, VMP therapy was associated with modest toxicity, a better response rate and prolonged survival, supporting the use of this effective combination as frontline therapy for very elderly patients with MM.