Cyclophosphamide, Bortezomib, and Dexamethasone Consolidation in Patients with Multiple Myeloma after Stem Cell Transplantation: The KMM130 Study

Purpose A three-drug combination of cyclophosphamide, bortezomib, and dexamethasone (CVD) shows significant efficacy and manageable toxicity as induction therapy in patients with multiple myeloma. Materials and Methods In this phase II study, we enrolled 45 patients who achieved a very good partial response (VGPR) or partial response (PR) after autologous stem cell transplantation (ASCT) and evaluated the efficacy and toxicity of CVD consolidation. CVD consolidation comprised three cycles of cyclophosphamide 300 mg/m² orally on days 1, 8, and 15, and bortezomib 1.3 mg/m² subcutaneously on days 1, 8, 15, and 22, along with dexamethasone 20 mg orally or intravenously on days 1 and 2, 8 and 9, 15 and 16, and 22 and 23. Results At enrollment, 39 patients (86.7%) showed VGPR, and nine (13.3%) presented with PR. Nineteen patients (45.2%) achieved a complete response or better as their best response after the end of consolidation. Overall, 22 of 42 patients (52.4%) experienced an improved response status with CVD consolidation. Three-year overall survival and progression-free survival rates were 89.0% and 42.7%, respectively. The most common non-hematologic toxicities were peripheral neuropathy and infection (20.5%), with no grade ≥ 3 neuropathy observed. Conclusion These results showed that CVD consolidation therapy improved the response with reasonable toxicity in patients with residual disease after ASCT. This trial was registered with the Clinical Research Information Service, Republic of Korea (KCT0001327).