Why Current HTA Frameworks Fall Short for Anti-Cancer Combination Therapies: Toward Equitable Value Attribution and Policy Reform
Author(s)
Jihyun Kang, R.N., B.S.1, Dong Eun Im, B.S.2, Minkyoung Kang, R.Ph., B.S.1, Hye-Young Kang, R.Ph., Ph.D.1.
1College of Pharmacy, Yonsei Institute of Pharmaceutical Science, Yonsei University, Incheon, Korea, Republic of, 2Department of Pharmaceutical Medicine and Regulatory Sciences, College of Medicine and College of Pharmacy, Yonsei University, Incheon, Korea, Republic of.
1College of Pharmacy, Yonsei Institute of Pharmaceutical Science, Yonsei University, Incheon, Korea, Republic of, 2Department of Pharmaceutical Medicine and Regulatory Sciences, College of Medicine and College of Pharmacy, Yonsei University, Incheon, Korea, Republic of.
OBJECTIVES: Combination therapies (CTs) are becoming essential in oncology to improve efficacy, expand treatment options, and reduce toxicity by avoiding high-dose monotherapy. However, conventional health technology assessment (HTA) frameworks—designed for single agents—struggle to fairly attribute value among drugs in a combination, hindering appropriate pricing and reimbursement. This study investigates the limitations of current HTA approaches and explores the policy considerations necessary for implementation.
METHODS: A scoping review was conducted across PubMed, Embase, and gray literature to identify methodological frameworks: (1) negotiation-based models such as the Briggs framework, which addresses real-world market dynamics through flexible value-sharing ranges, and (2) outcome-based models such as the segmented attribution model proposed by Towse. Among the models reviewed, this study focuses on describing and evaluating the Towse’s segmented model. In parallel, we analyzed industry perspectives using data from the 2024 Office of Health Economics (OHE) stakeholder survey.
RESULTS: The Towse model partitions total QALY-based health gain from a combination into three segments: (1) value shared by both agents, (2) value uniquely attributable to the backbone, and (3) value uniquely attributable to the add-on. It is considered fair and technically accurate across additive scenarios, but implementation is constrained by data requirements, including comparator arms. Survey insights highlighted feasibility, legal constraints, and data availability as key barriers to adoption.
CONCLUSIONS: As the clinical use of combination therapies expands, emerging value attribution frameworks must evolve in parallel to ensure fair and transparent reimbursement. While recent models—ranging from Briggs’ negotiation-based to Towse’s outcome-based approaches—offer theoretical improvements, their real-world implementation remains limited by structural and regulatory barriers. However, policy adaptations are needed, including flexible evidentiary thresholds, legal exemptions for inter-manufacturer negotiation, indication-based pricing, and provisional reimbursement mechanisms. Without these foundational reforms, even well-designed attribution models may fail to deliver equitable outcomes or incentivize innovation in oncology.
METHODS: A scoping review was conducted across PubMed, Embase, and gray literature to identify methodological frameworks: (1) negotiation-based models such as the Briggs framework, which addresses real-world market dynamics through flexible value-sharing ranges, and (2) outcome-based models such as the segmented attribution model proposed by Towse. Among the models reviewed, this study focuses on describing and evaluating the Towse’s segmented model. In parallel, we analyzed industry perspectives using data from the 2024 Office of Health Economics (OHE) stakeholder survey.
RESULTS: The Towse model partitions total QALY-based health gain from a combination into three segments: (1) value shared by both agents, (2) value uniquely attributable to the backbone, and (3) value uniquely attributable to the add-on. It is considered fair and technically accurate across additive scenarios, but implementation is constrained by data requirements, including comparator arms. Survey insights highlighted feasibility, legal constraints, and data availability as key barriers to adoption.
CONCLUSIONS: As the clinical use of combination therapies expands, emerging value attribution frameworks must evolve in parallel to ensure fair and transparent reimbursement. While recent models—ranging from Briggs’ negotiation-based to Towse’s outcome-based approaches—offer theoretical improvements, their real-world implementation remains limited by structural and regulatory barriers. However, policy adaptations are needed, including flexible evidentiary thresholds, legal exemptions for inter-manufacturer negotiation, indication-based pricing, and provisional reimbursement mechanisms. Without these foundational reforms, even well-designed attribution models may fail to deliver equitable outcomes or incentivize innovation in oncology.
Conference/Value in Health Info
2025-11, ISPOR Europe 2025, Glasgow, Scotland
Value in Health, Volume 28, Issue S2
Code
HTA370
Topic
Economic Evaluation, Health Technology Assessment
Topic Subcategory
Value Frameworks & Dossier Format
Disease
No Additional Disease & Conditions/Specialized Treatment Areas, Oncology