Cost-effectiveness of carfilzomib plus dexamethasone compared with bortezomib plus dexamethasone for patients with relapsed or refractory multiple myeloma in the United States.

BACKGROUND

We assessed the economic value of carfilzomib 56 mg/m2 and dexamethasone (Kd56) vs. bortezomib and dexamethasone (Vd) for relapsed/refractory multiple myeloma (R/RMM) using ENDEAVOR trial results.

METHODS

Cost-effectiveness of Kd56 vs. Vd was assessed using a partitioned survival model by estimating progression-free survival, overall survival, and direct costs over a lifetime horizon. Surveillance Epidemiology and End Results (SEER) survival data were extrapolated after matching registry and ENDEAVOR patients. Utilities were sourced from the literature and mapped from patient-reported quality of life in ENDEAVOR to estimate quality-adjusted life-years (QALYs) from life-years (LYs).

RESULTS

The model predicted an average gain of 1.66 LYs and 1.50 QALYs with Kd56 vs. Vd, and lifetime additional costs of $182,699, resulting in an incremental cost-effectiveness ratio (ICER) of $121,828/QALY gained. The ICER was $114,793/QALY in patients with 1 prior treatment; $99,263/QALY in those not transplanted, and <$150,000/QALY up to an 85% discount in bortezomib price.

CONCLUSIONS

Kd56 is cost-effective for patients with R/RMM at a willingness-to-pay threshold of $150,000/QALY. Trial data in the model may limit generalizability; however, SEER registry data mitigates this challenge. Kd56 provides additional value in key subgroups, and remains cost-effective after steep comparator discounts.