Cost-effectiveness of once weekly carfilzomib 70 mg/m2 plus dexamethasone in patients with relapsed and refractory multiple myeloma in the United States

Background: In the US, carfilzomib 70 mg⁄m² once-weekly plus dexamethasone (Kd70 QW) was recently indicated for relapsed and/or refractory multiple myeloma. In current US clinical practice, most patients treated with Kd receive carfilzomib at a previously approved dose of 27 mg/m² twice-weekly (Kd27 BIW). This analysis assessed the cost-effectiveness (CE) of Kd70 QW vs Kd27 BIW regimens which were compared in the randomized phase 3 ARROW trial. Methods: Based on clinical outcomes (overall survival and utilities) from ARROW, a partitioned survival model was developed to estimate life years (LYs) and quality-adjusted life years (QALYs). Long-term survival was extrapolated using SEER registry data matched to ARROW patients. Costs were estimated using a US healthcare payer perspective. Results: The analysis estimated that treatment with Kd70 QW vs Kd27 BIW resulted in an increase of 1.10 LYs, 0.91 QALYs, and additional lifetime costs of $74,858, yielding an incremental CE ratio (ratio of incremental costs to QALYs) of $82,257 per QALY gained. Results were robust to sensitivity and subgroup analyses. Conclusions: When compared with Kd27 BIW, Kd70 QW is the optimal dose that represents a cost-effective utilization of health care budget with incremental CE ratios well below the accepted willingness-to-pay thresholds in the US.