OBJECTIVES

To evaluate the cost-effectiveness of ribociclib for pre/perimenopausal women with HR-positive, HER2-negative advanced breast cancer.

METHODS

A cost-utility analysis was conducted from a US payer perspective using a partitioned survival model with three health states (progression-free (PF), progressed disease (PD), and death) over a 20-year time horizon. Weibull survival curves were fitted to parametrize and extrapolate Kaplan-Meier survival curves for both PF-survival and overall survival. Other clinical parameters, utilities, and disutilities were obtained from the RED BOOK®, Medicare Clinical Laboratory Fee Schedule, Medicare Physician Fee Schedule, and the literature. All costs were measured in 2019 US Dollars, and a 3% annual discount rate was applied. Effectiveness was measured in quality-adjusted life-years (QALYs) by adjusting gained life years with health state utilities. The main outcome measure was the incremental cost-effectiveness ratio (ICER), expressed as the incremental cost per QALY gained. One-way deterministic sensitivity analysis and Monte Carlo probabilistic sensitivity analysis were conducted to explore the model uncertainty. All modeling and computations were conducted using Stata/MP 15.1 and TreeAge Pro® 2019, R2 Software.

RESULTS

In the base case scenario, ribociclib plus endocrine therapy was associated with an average total cost of $433,958 and 4.09 QALYs as compared to the endocrine therapy alone of $44,795 and 2.69 QALYs. The ICER for ribociclib plus endocrine therapy compared to endocrine therapy alone was $279,534/QALY. One-way deterministic sensitivity analysis showed that ribociclib WAC price was a main model sensitive driver. Monte Carlo simulation of 10,000 iterations showed that at a willingness-to-pay threshold of $268,800, ribociclib plus endocrine therapy would surpass endocrine therapy alone as a cost-effective option.

CONCLUSIONS

Despite the significantly improved overall survival and progression-survival over endocrine therapy alone, ribociclib plus endocrine therapy for pre/perimenopausal patients with HR+, HER2- advanced breast cancer is not cost-effective at a willingness-to-pay threshold $100,000 or $150,000 per QALY in the United States.