An Economic Evaluation to Inform the Use of Enhanced Influenza Vaccines for Those Aged 65 Years and Older in the Seasonal Influenza Vaccination Program in Ireland
Author(s)
Susan Ahern, PhD.
Senior Health Economist, Health Information & Quality Authority of Ireland, Cork, Ireland.
Senior Health Economist, Health Information & Quality Authority of Ireland, Cork, Ireland.
OBJECTIVES: Enhanced inactivated influenza vaccines (IIVs) may offer benefits relative to a standard quadrivalent influenza vaccine (QIV). To inform the Seasonal Influenza Vaccination Programme in Ireland, a health technology assessment (HTA) requested by the Department of Health aimed to estimate the cost utility of vaccination with enhanced IIVs for those aged ≥65 years.
METHODS: An age-structured dynamic transmission model was developed analysing the transmission and incidence of notified cases of influenza and the impact of switching from a standard QIV to a high-dose (HD-IIV) or adjuvanted IIV (aIIV) for those aged ≥65 years. The wholesale costs of the vaccines to the healthcare system were unknown. Where list prices were not available, absolute and relative price data were sourced from the international literature. In the base-case analysis, prices of €10.99, €16.49 and €35.72 per dose were assumed for the standard QIV, aIIV and HD-IIV respectively. A 6-month time horizon and the publicly-funded healthcare system perspective were applied. Uncertainty was investigated using probabilistic sensitivity analysis and scenario analyses.
RESULTS: It was estimated that: - An aIIV-based strategy dominated the existing standard QIV-based strategy. - The incremental cost-effectiveness ratio for an HD-IIV based-strategy, compared with an aIIV-based strategy, exceeded the willingness-to-pay threshold of €45,000/QALY. Scenario analyses, assessing both incremental cost-effectiveness ratios and net monetary benefit of alternative vaccination strategies at varying vaccine prices, highlighted the considerable impact that the uncertainty regarding the relative costs of aIIV and HD-IIV, compared with standard QIV, had on the results of the cost-utility analysis (CUA).
CONCLUSIONS: This study highlighted the challenges of conducting a CUA of alternative vaccination strategies where the precise price of each vaccine is unknown. The HTA report provided to the Department of Health advised careful consideration of vaccine price in procurement negotiations with manufacturers and in associated decision-making regarding switching to an enhanced IIV.
METHODS: An age-structured dynamic transmission model was developed analysing the transmission and incidence of notified cases of influenza and the impact of switching from a standard QIV to a high-dose (HD-IIV) or adjuvanted IIV (aIIV) for those aged ≥65 years. The wholesale costs of the vaccines to the healthcare system were unknown. Where list prices were not available, absolute and relative price data were sourced from the international literature. In the base-case analysis, prices of €10.99, €16.49 and €35.72 per dose were assumed for the standard QIV, aIIV and HD-IIV respectively. A 6-month time horizon and the publicly-funded healthcare system perspective were applied. Uncertainty was investigated using probabilistic sensitivity analysis and scenario analyses.
RESULTS: It was estimated that: - An aIIV-based strategy dominated the existing standard QIV-based strategy. - The incremental cost-effectiveness ratio for an HD-IIV based-strategy, compared with an aIIV-based strategy, exceeded the willingness-to-pay threshold of €45,000/QALY. Scenario analyses, assessing both incremental cost-effectiveness ratios and net monetary benefit of alternative vaccination strategies at varying vaccine prices, highlighted the considerable impact that the uncertainty regarding the relative costs of aIIV and HD-IIV, compared with standard QIV, had on the results of the cost-utility analysis (CUA).
CONCLUSIONS: This study highlighted the challenges of conducting a CUA of alternative vaccination strategies where the precise price of each vaccine is unknown. The HTA report provided to the Department of Health advised careful consideration of vaccine price in procurement negotiations with manufacturers and in associated decision-making regarding switching to an enhanced IIV.
Conference/Value in Health Info
2025-11, ISPOR Europe 2025, Glasgow, Scotland
Value in Health, Volume 28, Issue S2
Code
EE47
Topic
Economic Evaluation, Epidemiology & Public Health
Disease
Respiratory-Related Disorders (Allergy, Asthma, Smoking, Other Respiratory), Vaccines