Canadian Retrospective Multicentric Study Comparing the Combination of Bortezomib, Cyclophosphamide and Dexamethasone (Cybord) Versus Bortezomib, Thalidomide and Dexamethasone (VTD) Versus Bortezomib and Dexamethasone (Vd) in Patients with Newly Diagnosed Multiple Myeloma Eligible for Autologous Hematopoietic Stem Cell Transplantation (HCT)
Authors: Yamga Eric , Leblanc Richard , Boudreault Jean-Samuel 
Published: October 2019

Abstract
Background: Multiple myeloma (MM) is the second most common hematologic cancer. The management of this disease consists of induction therapy followed by autologous hematopoietic stem cell transplantation (HCT). There is no standard of care as for the best induction regime. Recently, the first phase III study (Moreau P and all.) comparing two chemotherapy triplets in transplant-eligible patients, suggested a superiority of VTD over VCD. Although VTD was associated with better treatment response rates, the survival data remains to be seen. We wanted to retrospectively compare 3 Bortezomib-based therapies using response rates (RR), progression-free survival (PFS) and overall survival (OS). Bortezomib-Cyclophosphamide-Dexamethasone (CyBorD) remains the standard in Canada.
Method: A total of 75 patients induced between 2010 and 2016 were analyzed. Their charts were reviewed and the data was retrospectively collected. Three distinct treatment groups were included : Vd (19), CyBorD (39) and VTD (17).The main outcome was treatment response rate, 2-year progression-free survival rate (PFS) and 2-year overall survival rate (OS). The secondary outcome was median PFS.
Results: Patient characteristics are presented below (table 1). The difference between the treatment response rates were non-statistically significant but demonstrated a favorable trend towards VTD as the VGPR rate was 58.8%, 65% and 88.1% respectively in the Vd, CyBoRD and VTD groups (table 2 and 3). Median progression-free survival was significantly longer in the group that received VTD than in the group that received CyBord (3.58 years vs. 2,80 years; P = 0.03). The 2-year overall survival rate was 88,9%, 96,3% et 93,3% respectively in the 3 groups (table 4).
Conclusion: The data from this retrospective study supports the superiority of the VTD induction regimen compared with CyBorD and Vd in terms of response rate and progression-free survival. However, there is no major difference in overall survival over the time period observed.

Disclosures
Leblanc: Amgen Canada: Membership on an entity's Board of Directors or advisory committees; Takeda Canada: Membership on an entity's Board of Directors or advisory committees; Celgene Canada: Membership on an entity's Board of Directors or advisory committees; Janssen Inc.: Membership on an entity's Board of Directors or advisory committees. Boudreault:Celgen: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; Roche: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees.