OBJECTIVES: Study objective was to classify 28 European Union (EU) countries into clusters reflecting archetypes of market access pathways for vaccines, using mathematical algorithms.

METHODS: Description of market access pathway for vaccines was obtained through a comprehensive literature review and primary research among vaccines experts. Hierarchical clustering with agglomerative approach was applied considering the following attributes: applicability of horizon scanning, early advice, NITAG formal terms of reference and decision-analysis framework, level of decision-making, mandatory funding following inclusion in immunisation program, procurement type, level and transparency of tenders, number of vaccinations in immunisation program. Jaccard metrics was used to measure distance between countries and complete-linkage method was performed to measure distance between clusters. Optimal number of clusters was selected based on silhouette plot and appropriateness of clusters was checked by Dunn’s index and face validity.

RESULTS: Five clusters were identified through mathematical clustering and face validity. 1) National and sub-national decision-making & mandatory funding cluster (Belgium, Italy, Spain and Sweden) with population-based impact considered for recommendation on immunisation program on top of individual-based benefits, transparent tenders and shorter time to access, but without early advice for vaccines. 2) National decision-making without mandatory funding cluster (UK, being the one with truly influential NITAG, Malta and Cyprus) with horizon scanning and national tenders but without early advice for vaccines. 3) Individual reimbursement cluster (Czech, France, Germany, Greece and Slovakia) with national level of decision-making process. Remaining EU countries were classified as national decision-making & mandatory funding clusters with transparent tenders and either 4) higher or 5) lower median gross domestic product (GDP applied during face validity to split and balance clusters size).

CONCLUSIONS: The study helped to understand EU countries archetypes for vaccines market access to further support EU policy actions, driven by knowledge and best practice sharing for patients’ timely access.