Cost Effectiveness of Triplet Selinexor-Bortezomib-Dexamethasone (XVd) in Previously Treated Multiple Myeloma (MM) Based on Results from the Phase III BOSTON Trial

BACKGROUND AND OBJECTIVE: Nearly all patients with multiple myeloma undergo multiple rounds of therapy. The phase III BOSTON trial of once-weekly selinexor and once-weekly bortezomib with dexamethasone (XVd) vs twice-weekly bortezomib and dexamethasone (Vd) is the basis for this cost-effectiveness analysis in previously treated multiple myeloma from a US commercial payer perspective over a lifetime horizon. METHODS: A partitioned survival model enabled use of direct overall survival and progression-free survival curves from BOSTON to generate four health states for XVd and Vd: progression-free survival on treatment, progression-free survival off treatment, post-progression, and mortality. Using a 1-week cycle length, benefits and costs were discounted at 3.0% annually. Additional comparators were included in an exploratory analysis that compared XVd against seven additional regimens (six triplets, one doublet). RESULTS: After considering costs, utility, progression, and survival, the base-case incremental cost-effectiveness ratio of XVd vs Vd was $475,430/quality-adjusted life-year (QALY). The 50% cost-effectiveness probability midpoint was near $470,000/QALY, based on a probabilistic sensitivity analysis. The robustness of the analysis was supported by additional scenario assessment and deterministic and probabilistic sensitivity analyses, which generally demonstrated little variance, with greatest sensitivity to variations in discount rates and utility values. In an exploratory analysis against external comparators, XVd showed a higher QALY gain with a lower cost (i.e., dominance) compared with lenalidomide/dexamethasone (Rd), pomalidomide/bortezomib/dexamethasone (PVd), and carfilzomib/pomalidomide/dexamethasone (KPd). CONCLUSIONS: Addition of XVd to the previously treated multiple myeloma treatment landscape provides a novel oral treatment option, which, when compared to Vd in the base-case analysis resulted in an incremental cost-effectiveness ratio of $475,430/QALY. Exploratory analyses comparing against external comparators suggest that XVd was dominant vs Rd, PVd, and KPd. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40273-021-01068-9.