We present the cost-effectiveness analysis and the economic impact of the initial phase of the COVID-19 vaccination rollout in the Basque Country, Spain. To calculate costs and QALYs for the total Basque population, dynamical modelling and real-world data analysis were combined. The COVID-19 infection outcomes (cases, hospitalizations, intensive care unit admissions and deaths) and the population characteristics (age, sex, socioeconomic status and comorbidity) during the initial phase of vaccination rollout, from January to June of 2021, were retrieved from the Basque Health Service database. The outcomes in the alternative scenario (without vaccines) were obtained with the dynamical model used to assist the public health authorities, from February to December 2020. Individual comorbidity-adjusted life expectancy and costs were estimated.

Findings. COVID-19 vaccination in averting severe disease outcomes resulted a monetary saving of 26.44 million euros for the first semester of 2021. The incremental cost-effectiveness ratio (ICER) was €165/QALY (official vaccine prices) and dominant (real prices). Although no significant differences were observed by socioeconomic status, vaccines were more cost-effective in individuals with pre-existing health conditions. The distributional ICER of the vaccination program justified the policy to prioritize high risk patients. Our findings did not show inequity during the vaccination rollout in the Basque Country.