COST-EFFECTIVENESS OF ABEMACICLIB IN COMBINATION WITH FULVESTRANT IN WOMEN WITH HR+/HER2− ADVANCED BREAST CANCER AFTER PROGRESSION ON ENDOCRINE THERAPY IN JAPAN...
Author(s)
Zhonghua CHEN, BS1, Ryutaro Sakai, MS1, Seiya Taniguchi, MS1, Mao Yamaguchi, MS1, Kensuke Moriwaki, BS, MS, PhD2.
1Ritsumeikan University, Kusatsu, Japan, 2Associate Professor, Ritsumeikan University, Kyoto, Japan.
1Ritsumeikan University, Kusatsu, Japan, 2Associate Professor, Ritsumeikan University, Kyoto, Japan.
OBJECTIVES: Among patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer (ABC) who have progressed after endocrine therapy (ET), multiple subsequent treatment options are available. Although the MONARCH 2 clinical trial demonstrated superior clinical efficacy of abemaciclib plus fulvestrant compared with fulvestrant monotherapy, its cost-effectiveness in the Japanese healthcare setting remains unclear. This study evaluated the cost-effectiveness of abemaciclib plus fulvestrant versus fulvestrant alone in patients with HR-positive, HER2−negative ABC from the Japanese healthcare perspective.
METHODS: A partitioned survival analysis model was developed to estimate lifetime costs and quality-adjusted life years (QALYs) associated with abemaciclib plus fulvestrant and fulvestrant monotherapy. Survival inputs were derived from the phase III randomized controlled trial MONARCH 2 (NCT02107703). Drug acquisition costs were estimated using Japanese sales prices, while other medical costs were obtained from the JMDC claims database. A lifetime time horizon was applied, with both costs and health outcomes discounted at an annual rate of 2%. Health state and adverse event-related utility values were informed by published studies based on Japanese populations.
RESULTS: Compared with fulvestrant monotherapy, abemaciclib plus fulvestrant was associated with an incremental cost of JPY 20,821,257.30 and an incremental gain of 0.94 QALYs, resulting in an ICER of JPY 22,078,203.57 per QALY gained. Deterministic sensitivity analyses indicated that the ICER was most sensitive to the discount rate and the utility values of the progression-free survival (PFS) and progressed disease (PD) health states in the intervention group. Probabilistic sensitivity analysis estimated a 0% probability that abemaciclib plus fulvestrant would be cost-effective at a willingness-to-pay threshold of JPY 15 million per QALY.
CONCLUSIONS: At a willingness-to-pay threshold of JPY 15 million per QALY, abemaciclib plus fulvestrant was not cost-effective compared with fulvestrant monotherapy at current Japanese prices.
METHODS: A partitioned survival analysis model was developed to estimate lifetime costs and quality-adjusted life years (QALYs) associated with abemaciclib plus fulvestrant and fulvestrant monotherapy. Survival inputs were derived from the phase III randomized controlled trial MONARCH 2 (NCT02107703). Drug acquisition costs were estimated using Japanese sales prices, while other medical costs were obtained from the JMDC claims database. A lifetime time horizon was applied, with both costs and health outcomes discounted at an annual rate of 2%. Health state and adverse event-related utility values were informed by published studies based on Japanese populations.
RESULTS: Compared with fulvestrant monotherapy, abemaciclib plus fulvestrant was associated with an incremental cost of JPY 20,821,257.30 and an incremental gain of 0.94 QALYs, resulting in an ICER of JPY 22,078,203.57 per QALY gained. Deterministic sensitivity analyses indicated that the ICER was most sensitive to the discount rate and the utility values of the progression-free survival (PFS) and progressed disease (PD) health states in the intervention group. Probabilistic sensitivity analysis estimated a 0% probability that abemaciclib plus fulvestrant would be cost-effective at a willingness-to-pay threshold of JPY 15 million per QALY.
CONCLUSIONS: At a willingness-to-pay threshold of JPY 15 million per QALY, abemaciclib plus fulvestrant was not cost-effective compared with fulvestrant monotherapy at current Japanese prices.
Conference/Value in Health Info
2026-09, ISPOR Asia Pacific 2026, Bangkok, Thailand
Value in Health, Volume 55, Issue S1
Code
EE20
Topic
Economic Evaluation
Disease
SDC: Oncology