Bortezomib, thalidomide, and dexamethasone as induction therapy for patients with symptomatic multiple myeloma: a retrospective study.

BACKGROUND: This single-center retrospective study determined the efficacy of bortezomib, thalidomide, and dexamethasone (BTD) as induction for patients with multiple myeloma (MM) who were eligible for autologous stem cell transplantation (ASCT).

METHODS: Patients with symptomatic MM who had received BTD induction before stem cell collection at Winship Cancer Institute were included. BTD induction comprised up to 8 3-week cycles of bortezomib 1.3 mg/m(2) on Days 1, 4, 8, and 11; thalidomide 100 mg daily; and dexamethasone 40 mg on Days 1 through 4 and Days 9 through 12. Stem cell mobilization involved granulocyte-colony-stimulating factor and/or cyclophosphamide. Response was assessed according to European Group for Blood and Marrow Transplantation criteria.

RESULTS: Review of medical records identified 44 eligible patients (34 patients who were treated in the front-line setting and 10 patients who were treated for recurrent disease) who received a median of 4 BTD cycles. The overall response rate (ORR) was 91%, which included a greater than or equal to very good partial response (> or = VGPR) rate of 57% (including 20% stringent complete responses/complete response [sCR/CR] rate). In front-line patients, the ORR was 94%, which included a 56% > or = VGPR rate (24% sCR/CR). The median CD34-positive stem cell collection was 10.67 x 10(6)/kg. The ORR after ASCT in 34 patients who were evaluable for response was 100%, including a 76% > or = VGPR rate (53% sCR/CR). Among all 44 patients, the median progression-free survival (PFS) was 27.4 months. The median overall survival (OS) was not reached after a median follow-up of 25 months, and the 2-year OS rate was 82%. There were no significant differences in PFS (27.4 months vs 23.5 months) or in 2-year survival (80% vs 90%) between patients who did and did not undergo ASCT, respectively. Twenty patients (45%) developed neuropathy, including 4 (9%) with grade 3 neuropathy episodes, and 1 patient developed deep vein thrombosis.

CONCLUSIONS: BTD was highly effective and well tolerated as induction for MM patients who were eligible for ASCT. Long-term outcomes appeared to be similar with or without ASCT consolidation.