Background Few studies focused on the course of biotherapies in juvenile idiopathic arthritis (JIA). Results of these studies showed that anti-TNFalpha drug survival was comparable to adult rheumatoid arthritis. However, these JIA studies had short follow-up and focused only on anti-TNFalpha drug.
Objectives Determine the course of biotherapies and the risk factors for discontinuation in a large cohort of JIA at adulthood.
Methods A retrospective observational study of the use of biotherapies has been conducted in a large monocentric cohort of JIA patients at adulthood fulfilling ILAR criteria. Following data were collected: biotherapies treatments (Etanercept, Adalimumab, Abatacept, Tocilizumab and off label Infliximab, Anakinra and Rituximab), causes of discontinuation (adverse events, primary inefficacy, secondary inefficacy and inactive disease), age at diagnosis, uveitis, inflammatory bowel disease (IBD), psoriasis, presence of radiographic damages, coxitis, history of surgery, presence of antinuclear antibodies, rheumatoid factors, anti-CCP, and finally concomitant treatments of the biotherapy by corticosteroids or DMARDs.
Results 106 patients with JIA persisting at adulthood were included with a mean age of 22.5±9.7 years and a mean disease duration of 13.3±6.4 years. The mean follow-up since the start of biological treatment was 6.7±3.6 years and the mean number of biotherapies per patient was 2.2 [1-7].
49/106 (52%) patients needed only one biotherapy during all the course of their disease. Among these 49 patients, 43 (88%) patients remained on their first-line of biotherapy during all the course of the follow-up and only 6 (12%) could stop definitively their biotherapy.
Reasons for changing the first to the second line of biological treatment (n=57) were side effects (n=12), primary inefficacy (n=12), secondary inefficacy (n=22) and inactive disease (n=6) an others (n=5).
The mean duration of the first biological treatment was 44.5±41.4 [2-158] months, for the second biotherapy 28.8±28.4 [1-93] months and for the third biotherapy 15.5±15.8 [1-54] months. The duration of the first biological treatment was not influenced by the concomitant use of DMARDs or corticosteroids but the use of this latter was strongly associated with the risk to need switching from the first to a second line of biological treatment (81% vs 51%, p=0.001).
The risk factor for discontinuation of the first biological treatment was the presence of radiographic damages (p=0.04, OR=2.3 [1-5.2]). There was also a tendency for a lower age at diagnosis (p=0.08) and the systemic form of JIA (p=0.07) in JIA patients needing more than one biotherapy. No association was detected for sex, uveitis, IBD, psoriasis, antibodies status and surgery.
Conclusions In this large cohort of JIA patients at adulthood, more than half of patients remained on their first line of biological treatment after more than 6 years of treatment. The main risk factors for discontinuing the first biotherapy were inefficacy (primary or secondary) in 60% and as expected the percentage increased with the lines of treatments. Associated factor with the use of more than one biotherapy was an erosive form of JIA. Concomitant use of corticosteroids was associated with drug survival.
Disclosure of Interest None declared