OBJECTIVES

In the UK, patients who have severe rheumatoid arthritis (RA), defined as disease activity score in 28-joints (DAS28) >5.1, and have failed conventional therapy are eligible for advanced therapies. Typically, patients will initiate on a tumour necrosis factor inhibitor (TNFi). Progression to subsequent therapy classes is common following failure to respond or loss of efficacy. Challenges remain to navigate the affordability of new therapies in RA across six therapy classes. We explore the expected budget impact (BI) of the introduction of a novel janus kinase inhibitor, filgotinib, across the current treatment pathway in the UK.

METHODS

A prevalence-based BI model was developed to evaluate filgotinib as a treatment option in four scenarios, representing first to fourth line therapy. Strategies, comprising sequences of treatments, were based on a review of the British Society for Rheumatology Biologics Register for RA and the National Institute for Health and Care Excellence. The estimated distribution of patients across strategies was based on reported median time on treatment. BI analysis incorporated a healthcare payer perspective including drug acquisition, treatment administration, and monitoring costs over a 5-year time horizon for a hypothetical cohort.

RESULTS

For all scenarios, filgotinib (200mg) was estimated to result in savings from treatment administration and monitoring from £28 to £1,485 per patient over a 5-year period. First line initiation with filgotinib resulted in a range from savings of £1,086 to additional cost of £234 per patient. The BI of replacing TNFi cycling at second line with filgotinib ranged from savings of £330 to additional costs of £1,928. At third line the magnitude of potential savings increases to £4,821. Switching to filgotinib at fourth line results in savings for all pairwise comparisons undertaken.

CONCLUSIONS

Incorporating the distribution of patients across treatment sequences impacts the magnitude of the estimated budget impact following the introduction of novel therapies.