OBJECTIVES

Juvenile idiopathic arthritis (JIA) represents seven forms of chronic arthritis in children. Inadequately treated, it may result in lifelong disability. Treatment of JIA usually involves methotrexate (MTX) as first-line therapy, and (more costly) biologics as second-line treatment. However, in systemic JIA, biologics are used as first-line treatment. To achieve adequate disease control, many different combinations and sequences of medication may be necessary. This study aims to describe different lines of treatment for JIA patients and to quantify the accompanying impact on drug costs.

METHODS

A cohort of 884 JIA patients (0-18 years), treated in the Wilhelmina Children’s Hospital (the Netherlands), between 04/2011 and 04/2019 was analysed. Data on the type, frequency and duration of medication prescribed to these patients were retrieved from the hospital administrative system. Prescribed doses and accompanying cost prices were retrieved from the Dutch Pharmacotherapeutic Compass and the Dutch paediatric formulary, to calculate the average annual costs of medication per patient.

RESULTS

Twenty different (combinations of) drugs were used as first-line treatment, compared with 35 as second-line treatment. Oral MTX was the most commonly prescribed first-line treatment (56.7% of patients), compared with 39.1% in second-line (including combination therapies). On average, patients receive 2.3 lines of treatment during an average 4.4 year follow-up period. The average annual costs/patient range from €93 for undifferentiated JIA to €8,676 for systemic JIA. This difference was mainly attributable to the high costs of biologics (84.7% of total drug costs). Canakinumab was only used among systemic JIA patients and by far the most expensive, costing on average €60,156/patient/year over the entire follow-up period.

CONCLUSIONS

Pharmacological treatment of JIA is complex and warrants an individualized approach. Systemic JIA represents the subgroup with the highest medication costs, which is attributable to 1) the use of biologics, 2) the use of canakinumab, which is restricted to systemic JIA patients.