Once- versus twice-weekly Bortezomib induction therapy with dexamethasone in newly diagnosed multiple myeloma.

In this study, we administered a modified schedule of weekly intravenous Bortezomib at 1.6 mg/m(2) with dexamethasone (BD) and compared it to the standard 1.3 mg/m(2) twice-weekly BD regimen in Chinese patients with newly diagnosed multiple myeloma (MM). We assessed the difference in efficacy, safety profile and survival between the once-weekly and twice-weekly cohorts (13 vs. 24 patients). The over response rate was similar with both arms of the study, being 77% in the once-weekly schedule and 74.9% in the twice-weekly schedule (P=0.690). The median overall survival was not reached in either schedule. Also, the median progression-free survival and duration of response of the once-weekly schedule did not significantly differ from those of the twice-weekly schedule (8 months vs.10 months, P=0.545 and 6 months vs.7 months, P=0.467 respectively). Peripheral sensory neuropathy and grade 3/4 hematologic toxic effects were more frequently reported in the twice-weekly schedule than the once-weekly schedule, but there was no statistically significant difference. This preliminary experience in Chinese patients with newly diagnosed MM indicated that once-weekly infusion of Bortezomib plus dexamethasone may improve safety without affecting outcome.