Long-Term Follow-Up of Autotransplantation Trials for Multiple Myeloma: Update of Protocols Conducted by the Intergroupe Francophone du Myelome, Southwest Oncology Group, and University of Arkansas for Medical Sciences

Abstract

Purpose The purpose of this study was to update outcomes of autotransplantation trials for myeloma conducted by the Intergroupe Francophone du Myelome (IFM), the Southwest Oncology Group, and the University of Arkansas for Medical Sciences (Total Therapy [TT]). Methods IFM90 (N = 194), IFM04 (N = 402), IFM9902 (N = 692), IFM9904 (N = 197), S9321 (N = 817), TT1 (N = 231), TT2 (N = 668), and TT3 (N = 303) were updated, and results were compared with original reports. Results Superior survival with single transplantation versus standard therapy in IFM90 was confirmed (P = .004), and a trend in favor of tandem versus single transplantation was maintained in IFM94 (P = .08). S9321 data were validated, with comparable survival in single transplantation and standard treatment arms (P = .35). A survival benefit from thalidomide maintenance in IFM9902 was not confirmed (P = .39) but emerged for the thalidomide arm of TT2 (P = .04). On multivariate analysis, survival was superior in TT2, TT3, and IFM9902 (all P < .001); tandem transplantations were superior to both single transplantations and standard therapies (P < .001), as were tandem transplantations with added thalidomide versus trials without thalidomide (P < .001). Postrelapse survival (PRS) was superior when initial event-free survival (EFS) exceeded 1280 days and when tandem transplantations had been administered, whereas PRS was shorter when EFS lasted 803 days or less and when trials had included thalidomide and bortezomib. Conclusion These long-term follow-up data of transplantation trials provide a crucial framework of reference for outcome reporting of novel agent–based trials reportedly exhibiting remarkable short-term efficacy approaching high-dose therapy results.