Bortezomib-thalidomide-dexamethasone-cisplatin-doxorubicin-cyclophosphamide-etoposide as a Salvage and Bridging Regimen before Hematopoietic Stem Cell Transplantation for Relapsed or Refractory Multiple Myeloma

OBJECTIVE: Currently, treatment of relapsed or refractory multiple myeloma is challenging. Although bortezomib-thalidomide-dexamethasone-cisplatin-doxorubicin-cyclophosphamide-etoposide (VTD-PACE), a potent combination of a proteasome inhibitor, immunomodulatory drug, and conventional chemotherapeutics, is a widely used regimen, its efficacy and safety are unclear. METHODS: We retrospectively analyzed the clinical data of 35 patients treated with VTD-PACE. RESULTS: The overall response rate was 65.7% (complete response, 5.7%). The median progression-free survival (PFS) and overall survival (OS) were 8.0 [95% confidence interval (CI), 0.9-15.0] and 20.0 (95% CI, 17.5-22.5) months, respectively. Twenty-two (62.9%) patients developed grade 3-4 infections, and no therapy-related deaths occurred. Sixteen of 25 patients (64%) underwent stem cell harvest successfully with more than 2.0×10(6)/kg of CD34 cells after VTD-PACE. Twenty-two patients underwent autologous or allogeneic stem cell transplantation (SCT). The response and survival durations were short in patients without SCT after VTD-PACE [median PFS: 4.0 (95% CI, 2.7-5.3) months; OS: 14.0 (6.9-21.0) months]; however, these responses significantly improved with SCT following VTD-PACE. The PFS was 8.0 (NA) months (p=0.024), and the OS was 21.0 (19.1-22.8) months (p=0.019). CONCLUSION: VTD-PACE is an effective and tolerable salvage regimen and feasible bridging therapy for SCT.