High response rate to bortezomib with or without dexamethasone in patients with relapsed or refractory multiple myeloma: Results of a global phase 3b expanded access program

Abstract

Phase 2 trials have demonstrated that bortezomib ± dexamethasone is safe and effective in relapsed multiple myeloma (MM). In this multicentre, open-label, phase 3b trial, 638 patients with relapsed or refractory MM (median 3 prior therapies) received bortezomib 1.3 mg/m2 on days 1, 4, 8, and 11 of a maximum of eight 3-week cycles (median 5 cycles). Dexamethasone 20 mg/d was added the day of and day after each bortezomib dose for progressive disease after ≥2 cycles or for stable disease after ≥4 cycles. Responses were assessed based on M-protein changes. Overall response rate was 67%, including 11% complete (100% M-protein reduction), 22% very good partial (75-99% reduction), 18% partial (50-..