Cost-effectiveness analysis of quadrivalent influenza vaccination in at-risk adults and the elderly: an updated analysis in the UK

Abstract

Objective:

To update an earlier evaluation estimating the cost-effectiveness of quadrivalent influenza vaccination (QIV) compared with trivalent influenza vaccination (TIV) in the adult population currently recommended for influenza vaccination in the UK (all people aged ≥65 years and people aged 18–64 years with clinical risk conditions).

Methods:

This analysis takes into account updated vaccine prices, reference costs, influenza strain circulation, and burden of illness data. A lifetime, multi-cohort, static Markov model was constructed with seven age groups. The model was run in 1-year cycles for a lifetime, i.e., until the youngest patients at entry reached the age of 100 years. The base-case analysis was from the perspective of the UK National Health Service, with a secondary analysis from the societal perspective. Costs and benefits were discounted at 3.5%. Herd effects were not included. Inputs were derived from systematic reviews, peer-reviewed articles, and government publications and databases. One-way and probabilistic sensitivity analyses were performed.

Results:

In the base-case, QIV would be expected to avoid 1,413,392 influenza cases, 41,780 hospitalizations, and 19,906 deaths over the lifetime horizon, compared with TIV. The estimated incremental cost-effectiveness ratio (ICER) was £14,645 per quality-adjusted life-year (QALY) gained. From the societal perspective, the estimated ICER was £13,497/QALY. A strategy of vaccinating only people aged ≥65 years had an estimated ICER of £11,998/QALY. Sensitivity analysis indicated that only two parameters, seasonal variation in influenza B matching and influenza A circulation, had a substantial effect on the ICER. QIV would be likely to be cost-effective compared with TIV in 68% of simulations with a willingness-to-pay threshold of <£20,000/QALY and 87% with a willingness-to-pay threshold of <£30,000/QALY.

Conclusions:

In this updated analysis, QIV was estimated to be cost-effective compared with TIV in the UK.

Keywords::

• Cost-effectiveness
• Quadrivalent
• Seasonal influenza
• Trivalent
• UK
• Vaccination

Transparency

Declaration of funding

This study was funded by GlaxoSmithKline Biologicals SA, which was involved in all stages of the study conduct and analysis including: design and operation of the model; data inputs, analysis and interpretation; manuscript preparation, review and decision to submit for publication. GlaxoSmithKline Biologicals SA also funded all costs associated with the development and the publishing of the present manuscript. All authors had full access to the data and agreed with the submission of the publication.

Declaration of financial/other relationships

GM and MG are employees of the GSK group of companies. GM holds shares in the GSK group of companies and held stock options in the GSK group of companies until July 2013. BPN reports personal fees from the GSK group of companies during the conduct of the study and outside the submitted work. JME peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Acknowledgments

The authors would like to thank Carole Nadin (Fleetwith Ltd, on behalf of GSK Vaccines) for medical writing assistance and Carole Desiron (Business and Decision Life Sciences, on behalf of GSK Vaccines) for publication co-ordination. The authors also thank Ilse Van Vlaenderen and Laure-Anne Van Bellinghen (CHESS In Health, Belgium) for their contributions to the development of the model and the original publication.

Notes

*Fluarix Tetra is a trademark of the GSK group of companies.