High Complete and Very Good Partial Response Rates with Bortezomib—Dexamethasone as Induction Prior to ASCT in Newly Diagnosed Patients with High-Risk Myeloma: Results of the IFM2005-01 Phase 3 Trial.

Abstract 353 In the setting of high-dose therapy (HDT) plus ASCT for MM, achievement of a complete (CR) or VGPR is associated with prolonged PFS and overall survival, and thus represents a major goal of treatment; in the IFM99 trials, achievement of ≥VGPR was significantly correlated to outcome (Harousseau et al, JCO 2009, in press). We have previously reported results from the IFM2005-01 randomized phase 3 study of bortezomib (Velcade®)–dexamethasone (VD) vs VAD as induction therapy prior to HDT-ASCT showing that induction with VD yields significantly higher CR and CR+VGPR rates vs VAD, both before and after HDT-ASCT (Harousseau et al, ASCO 2008). Here we report PFS overall in patients receiving VAD or VD induction, and according to post-induction and post-HDT-ASCT response (≥VGPR vs 3 vs ≤3 mg/L) and chromosome 13 abnormalities (del13) by fluorescence in situ hybridization (FISH). Responses were evaluated post-induction and post-HDT-ASCT according to modified EBMT criteria (incorporating near-CR [nCR] and VGPR). Patients achieving 5.5) vs Stage I/II (median 29.8 vs 36.5 months, p=0.1191), and patients with vs without t(4;14) ± del17p (median 33.5 vs 36.5 months, p=0.1655). These data suggest that induction with VD might partially overcome the poor prognosis associated with ISS Stage III MM, and presence of t(4;14) ± del17p. In conclusion, in this trial achievement of at least VGPR after induction appears to be a major prognostic factor. Apparent improvement in PFS obtained with VD vs VAD induction might be related to higher ≥VGPR rate, across all prognostic subgroups including patients with poor-risk characteristics. Disclosures: Harousseau: Janssen Cilag: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees. Attal:Janssen Cilag: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees. Hulin:Janssen-Cilag: Honoraria; Celgene: Honoraria. Facon:Janssen-Cilag: Membership on an entity's Board of Directors or advisory committees; Johnson and Johnson: Membership on an entity's Board of Directors or advisory committees. Webb:Johnson & Johnson: Employment, Equity Ownership. Moreau:Celgene: Membership on an entity's Board of Directors or advisory committees; Millennium: Membership on an entity's Board of Directors or advisory committees.