8516 Background: Cytoreductive induction followed by HD-MEL and ASCT is considered standard of care for younger patients (pts) with multiple myeloma (MM). The success of this combined procedure partially depends on the efficacy of induction treatment. Bortezomib-containing induction regimens have already been shown to be superior to standard VAD. In order to further improve the efficacy of induction treatment we combined Vel with intravenous (IV) cyclophosphamide (C) and dexamethasone (D). Methods: This trial is an open, prospective, multicenter, uncontrolled phase II/III study with a planned recruitment of 400 pts. The first 30 pts were included in the dose finding study to determine the optimum dose of IV C in conjunction with Vel and D. The following 170 pts up to 60 years of age with untreated MM were enrolled to receive 3 cycles of induction with Vel 1.3 mg/m2 IV d1, 4, 8, 11; D 40 mg/d d1, 2, 4, 5, 8, 9, 11, 12; and C 900mg/m2 IV d1. Primary study objective is response rate (≥ PR) to VelCD according to the EBMT criteria. Results: Data from the first completed 200 pts (mean age: 52 years; 74% stage III) from 36 German centers were analyzed as ITT population. Response rates are given in Table and were documented in 82% of the subjects with 13q-, in 94% with t(4;14) and in 70% with 17p-. SAEs (n=84) occurred in 24.5% of the pts and were related to Vel, C or D in 16%, 14.5% or 9.5% respectively. The mortality rate of 1% is low, 53% of the patients experienced grade 3 + 4 AEs, infections of grade 3 and 4 were reported in 2% and grade 3 paraesthesia occurred in 2%. Conclusions: This interim analysis demonstrates that bortezomib combined with dexamethasone and intravenous cyclophosphamide (VelCD) is a highly effective induction regimen for pts ≤ 60 years with newly diagnosed MM regardless of cytogenetic risk factors. [Table: see text] [Table: see text]