THE HIDDEN IMPACT OF CONFIDENTIAL REBATES ON HEALTH TECHNOLOGY ASSESSMENT: A COST-EFFECTIVENESS CASE STUDY IN TAIWAN
Author(s)
Chen-Han Chueh, PhD1, Hsiao-Ling Chen, MS2, Li-Jiuan Shen, PhD3, Yi-Wen Tsai, PhD2.
1University of California San Diego, San Diego, CA, USA, 2National Yang Ming Chiao Tung University, Taipei, Taiwan, 3National Taiwan University, Taipei, Taiwan.
1University of California San Diego, San Diego, CA, USA, 2National Yang Ming Chiao Tung University, Taipei, Taiwan, 3National Taiwan University, Taipei, Taiwan.
OBJECTIVES: Since 2012, Taiwan’s National Health Insurance (NHI) has used confidential rebate-based managed entry agreements (MEAs) to reduce the budget impact of innovative drugs, particularly cancer therapies. Annual rebates increased from NT$7.9 million to NT$55.7 million in 2021. However, the confidentiality of MEAs may affect stakeholder decision-making. This study uses advanced intrahepatic cholangiocarcinoma as a case study to illustrate how confidential rebates for comparators can influence economic evaluations of new drugs.
METHODS: A three-state partitioned survival model evaluated the lifetime cost-effectiveness of futibatinib versus NHI-reimbursed pemigatinib. Efficacy inputs were derived from digitized progression-free and overall survival curves from FOENIX-CCA2 and FIGHT-202. Futibatinib’s price was estimated from pemigatinib’s listed price using UK price ratios. Utility, disutility, and other direct medical costs were sourced from the literature. The willingness-to-pay threshold was three times Taiwan’s 2023 GDP per capita (NT$3,023,055). Five scenarios assumed pemigatinib’s pharmaceutical cost to be 90% to 50% of the base-case value, reflecting potential confidential rebates under the MEA. Deterministic and probabilistic sensitivity analyses were performed.
RESULTS: Compared with pemigatinib, futibatinib increased costs by NT$498,059 and QALYs by 0.17, resulting in a positive incremental net monetary benefit (INMB) of NT$7,264 and a 52.4% probability of cost-effectiveness. With a simulated 10% rebate for pemigatinib, futibatinib’s incremental cost rose to NT$633,655, the INMB became negative (−NT$128,332), and the probability of cost-effectiveness fell to 48.2%. As the simulated rebate increased from 20% to 50%, the INMB declined further, ranging from −NT$263,928 down to −NT$670,716.
CONCLUSIONS: Failing to account for confidential comparator rebates under MEAs in health technology assessment may overestimate the value of a new drug, mislead stakeholder expectations, and distort policy decisions. In the absence of a predictable rebate range or consistent rebate principles, scenario analysis is essential to inform new drug valuation and decision-making by both industry and policymakers.
METHODS: A three-state partitioned survival model evaluated the lifetime cost-effectiveness of futibatinib versus NHI-reimbursed pemigatinib. Efficacy inputs were derived from digitized progression-free and overall survival curves from FOENIX-CCA2 and FIGHT-202. Futibatinib’s price was estimated from pemigatinib’s listed price using UK price ratios. Utility, disutility, and other direct medical costs were sourced from the literature. The willingness-to-pay threshold was three times Taiwan’s 2023 GDP per capita (NT$3,023,055). Five scenarios assumed pemigatinib’s pharmaceutical cost to be 90% to 50% of the base-case value, reflecting potential confidential rebates under the MEA. Deterministic and probabilistic sensitivity analyses were performed.
RESULTS: Compared with pemigatinib, futibatinib increased costs by NT$498,059 and QALYs by 0.17, resulting in a positive incremental net monetary benefit (INMB) of NT$7,264 and a 52.4% probability of cost-effectiveness. With a simulated 10% rebate for pemigatinib, futibatinib’s incremental cost rose to NT$633,655, the INMB became negative (−NT$128,332), and the probability of cost-effectiveness fell to 48.2%. As the simulated rebate increased from 20% to 50%, the INMB declined further, ranging from −NT$263,928 down to −NT$670,716.
CONCLUSIONS: Failing to account for confidential comparator rebates under MEAs in health technology assessment may overestimate the value of a new drug, mislead stakeholder expectations, and distort policy decisions. In the absence of a predictable rebate range or consistent rebate principles, scenario analysis is essential to inform new drug valuation and decision-making by both industry and policymakers.
Conference/Value in Health Info
2026-11, ISPOR Europe 2026, Vienna, Austria
Value in Health, Volume 29, Issue 12S
Code
EE72
Topic
Economic Evaluation, Health Policy & Regulatory, Health Technology Assessment
Disease
Oncology, Personalized & Precision Medicine, Rare & Orphan Diseases