Method: Cost-effectiveness and cost-utility analyses were used to compare oseltamivir to usual care (symptomatic treatment with over the counter (OTC) medicine), considering both the societal and health care payers perspectives. The population group studied was otherwise healthy adolescents and adults, aged 13 to 64. Danish data were collected to simulate results that are specific to Denmark. The economic model included first- and second-order Monte Carlo simulations. Sensitivity analyses were conducted to test the robustness of the analyses.

Main outcome measure: The cost-effectiveness study was expressed as gain in cost per day to return to normal activity, and the cost-utility study as cost per QALY (quality adjusted life years) gained.

Results: From a societal perspective, oseltamivir was a dominant treatment compared to usual care. From a health care payers perspective, the cost-effectiveness ratio was |CE 12.3 per gain in day to return to normal activity and |CE 5,063 /QALY gained. A sensitivity analysis leaving out hospitalisation, complications, and mortality showed increased cost-effectiveness and cost-utility ratios. However, treatment with oseltamivir remained cost-effective, assuming a willingness to pay for health benefits at |CE 26,174/QALY.

Conclusion: Pharmacoeconomic analyses of influenza treatment with oseltamivir in an otherwise healthy Danish adolescent/adult population show that this treatment saves money for society and is associated with a relatively low cost from a health care payers perspective. Treatment of influenza with oseltamivir would be cost-effective for healthy adolescents/adults in Denmark.