OBJECTIVES: This study aims to examine how differences in policy measures and practices between regions in the United Kingdom (UK) influence market dynamics of biosimilar and originator infliximab and etanercept.

METHODS: First, a literature review on (biosimilar) policies in the UK was conducted. Second, market data provided by the NHS on biosimilar and originator infliximab and etanercept uptake were analysed for the 10 historical regions of England, 14 health boards in Scotland and 7 health boards in Wales (Q1 2015 to Q3 2018). Third, findings were discussed in ten interviews: on a national level with an industry representative (1), on a regional level with NHS employees in England (6), Scotland (1), and Wales (1), and on a local level with a representative of a Trust in England (1).

RESULTS: During the study period, biosimilars were the most cost-effective option for treatment with infliximab or etanercept in England, Scotland and Wales. Early and late biosimilar adopters are seen, with overall convergence towards high biosimilar market shares. Qualitative results suggest that biosimilar uptake is positively influenced by: a) a good relationship between commissioner and provider in England resulting in gainsharing agreements; b) a price difference between biosimilar and originator product making it worth to switch patients; c) leadership on biosimilars in regional NHS offices in England or Scottish and Welsh health boards; and d) key opinion leaders or leading hospitals that start using biosimilars early and gain experience. Even if no gainsharing agreement is in place (Scotland, Wales), high biosimilar market shares are reached, emphasising the role of demand-side policies like guidelines and educational initiatives.

CONCLUSIONS: This study has shown that the savings potential drives biosimilar use. Some regions adopted biosimilars more quickly, but over time most regions reached high biosimilar market shares. Any differences in biosimilar market shares arose from multiple factors.