Estimated cost-effectiveness and burden of disease associated with quadrivalent cell-based and egg-based influenza vaccines in Spain.

Influenza is a viral respiratory disease that causes significant clinical and economic burden globally. Quadrivalent influenza vaccine (QIV) is frequently used to protect people who have a high-risk of developing influenza complications due to comorbidities. QIV offers protection against influenza A (A/H1N1 and H3N2) and B (B/Victoria, and B/Yamagata) strains. The European Medicines Agency has recently approved a cell-based QIV (QIVc) in people aged over 9 years old. QIVc has been shown to be more effective at preventing influenza than traditional egg-based QIV (QIVe). In this study, we use a health economic model adapted to Spain to assess the costs and outcomes associated with using QIVc instead of QIVe in people aged 9-64 at high-risk of complications. Observed vaccine coverage of 32% in the 9-17 age group, 17% in those aged 18-59, and 22% for ages 60-64 was used in the analysis. In total, 2.5 million people were vaccinated in the simulations. Using QIVc instead of QIVe was associated with 16,221fewer symptomatic cases, 4,522 fewer primary care visits, 1,015 fewer emergency room visits and 88 fewer hospitalizations. From a societal perspective, QIVc was more effective and less expensive compared to QIVe, leading to a cost-saving of €3.4 million. From a public payer perspective, the incremental cost-effectiveness ratio for QIVc vs QIVe was €12,852 per QALY gained. In conclusion, QIVc offers a cost-effective alternative to QIVe and should be considered as an alternative vaccine to QIVe for people aged 9-64 at high-risk of influenza complications in Spain.

Formulation Design, Optimization and In Vivo Evaluations of an α-Tocopherol-Containing Self-Emulsified Adjuvant System using Inactivated Influenza Vaccine.

α-Tocopherol has been used as an immune supplement in humans, as an emulsion adjuvant component in several veterinary vaccines as well as an immunomodulatory component of AS03, an emulsion adjuvant that was used in an H1N1 pandemic vaccine (Pandemrix). AS03 is manufactured using microfluidization and high-pressure homogenization. Such high energy and complex manufacturing processes make it difficult and expensive to produce emulsion adjuvants on a large scale, especially in developing countries. In this study we have explored simpler, comparatively inexpensive methods, to formulate emulsion adjuvants containing α-tocopherol, that have the potential to be made in any well-established scale-up facility. This might facilitate producing and stock-piling adjuvant doses and therefore aide in pandemic preparedness. We used design of experiment as a tool to explore incorporating α-tocopherol into self-emulsified systems containing squalene oil and polysorbate 80. We created novel self-emulsified adjuvant systems (SE-AS) and evaluated their potency in vivo in BALB/c mice with inactivated quadrivalent influenza vaccine (QIV) and tested the cellular and humoral immune responses against the four vaccine strains.

Cost-effectiveness analysis of quadrivalent versus trivalent influenza vaccine in Taiwan: A lifetime multi-cohort model.

A government-funded trivalent influenza vaccine (TIV) program to prevent seasonal influenza was implemented in Taiwan since 1998. However, mismatch between the vaccine and circulating strains may occur. Alternatively, a quadrivalent influenza vaccine (QIV) includes all 4 influenza lineages could minimize the risk of mismatches. Therefore, QIV could be considered as an alternative strategy to enhance protection against seasonal influenza. The objective of the study was to analyze, from a governmental perspective, the cost-effectiveness of using QIV vs. TIV as a vaccination strategy in Taiwan. A lifetime multi-cohort, static Markov model was constructed with 9 age groups to assess the costs and effectiveness of QIV vs. TIV. Direct costs were obtained from a database released by the Ministry of Health and Welfare. Outcomes included life-years gained, quality-adjusted life years (QALYs) gained, influenza cases avoided and incremental cost-effectiveness ratios (ICERs). The discount rate of costs and effectiveness was set at 3.5% and the time horizon used in the model was 100 y. Results show that a vaccination strategy utilizing QIV instead of TIV would bring an additional 10,557 QALYs at an extra cost of US$39.4 million, yielding an ICER of US$3,015.07 per QALY gained. When setting the willingness-to-pay threshold at US$10,000, compared to TIV, the probability that QIV would be cost-effective was 98%. Sensitivity analyses show that ICER was sensitive to the changes of circulation of influenza virus subtypes and vaccine mismatch. From a governmental perspective, the QIV vaccination could be considered as a cost-effective strategy within the context of public health in Taiwan.