Bortezomib-Thalidomide-Dexamethasone Versus Thalidomide-Dexamethasone before and after Double Autologous Stem Cell Transplantation for Newly Diagnosed Multiple Myeloma: Final Analysis of Phase 3 Gimema-MMY-3006 Study and Prognostic Score for Survival Outcomes

Introduction: The phase 3 GIMEMA-MMY-3006 trial comparing bortezomib-thalidomide-dexamethasone (VTD) versus thalidomide-dexamethasone (TD) as induction therapy before, and consolidation after, double autologous stem cell transplantation (ASCT) for newly diagnosed multiple myeloma (MM) provided the first demonstration of increased CR rate, the primary study endpoint, and prolonged PFS with VTD (Cavo M et al, Lancet 2010). However, updating trial results with longer follow-up than earlier reported is needed to assess the effects of treatment interventions on OS and to identify factors predicting for favorable long term outcomes. Aims: We performed a post-hoc analysis of that study to evaluate long term results and construct a prognostic index of survival. Methods: 474 patients were enrolled, 236 randomized to VTD and 238 to TD. Median follow-up for surviving patients was 124 months (IQR: 117-131). Analyses were performed on an intention-to-treat basis. Semi-parametric Cox regression analysis was used to construct the prognostic index. To assess the evolution of prognosis over time, conditional survival CS(t|s) estimate for PFS was calculated as the probability of surviving without progression a further 2 (t) years (yrs) after having already survived s yrs. Results: Estimates of PFS and OS at 10 yrs for the VTD arm were 34% (HR=0.62; 95% CI=0.50-0.77; p Conclusions: With a follow up of 10 yrs, the final analysis of the GYMEMA MMY-3006 trial comparing VTD versus TD showed a persistent PFS benefit translating into extended OS for the VTD arm. A prognostic model based on cytogenetic, ISS stage and achievement of CR, identified three risk groups with statistically different long-term survival probabilities. Both IR and HR groups significantly benefited from VTD. A PFS time of 78 months predicted for long term survival outcomes in the LR and IR groups. Disclosures Tacchetti: Celgene: Honoraria; Janssen: Honoraria; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; BMS: Honoraria; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees. Di Raimondo:Takeda: Honoraria, Research Funding; Celgene: Honoraria. Zamagni:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees. Bringhen:Bristol-Myers Squibb: Honoraria; Celgene: Honoraria; Amgen: Honoraria, Other: Advisory Board; Janssen: Honoraria, Other: Advisory Board; Takeda: Consultancy. Offidani:Celgene: Honoraria, Other: Advisory Board; Janssen: Honoraria, Other: Advisory Board; Amgen: Honoraria, Other: Advisory Board; Bristol-Myers Squibb: Honoraria, Other: Advisory Board; Takeda: Honoraria, Other: Advisory Board. Montefusco:Celgene: Other: Advisory Board; Amgen: Other: Advisory Board; Janssen: Other: Advisory Board. Cavo:Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Adaptive Biotechnologies: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; GlaxoSmithKline: Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie: Honoraria, Membership on an entity's Board of Directors or advisory committees.