Mourao, Ana F.Santos, Maria J.Melo Gomes, Jose A.Martins, Fernando M.Mendonca, Silvia C.Ramos, Filipa OliveiraFernandes, SusanaSalgado, ManuelGuedes, MargaridaCarvalho, SoniaCosta, Jose A.Brito, IvaDuarte, CatiaFurtado, CarolinaLopes, AnaRodrigues, AnaSequeira, GracaBranco, Jaime C.Fonseca, Joao E.Canhao, Helena2017-04-072017-04-072016-041462-0324http://hdl.handle.net/10400.1/9533Methods. We prospectively collected patient and disease characteristics from patients with JIA who started biological therapy. Adverse events were collected during the follow-up period. Predictors of response at 1 year and drug retention rates were assessed at 4 years of treatment for the first biologic agent.Results. A total of 812 JIA patients [65% females, mean age at JIA onset 6.9 years (s.d. 4.7)], 227 received biologic therapy; 205 patients (90.3%) were treated with an anti-TNF as the first biologic. All the parameters used to evaluate disease activity, namely number of active joints, ESR and Childhood HAQ/HAQ, decreased significantly at 6 months and 1 year of treatment. The mean reduction in Juvenile Disease Activity Score 10 (JADAS10) after 1 year of treatment was 10.4 (s.d. 7.4). According to the definition of improvement using the JADAS10 score, 83.3% respond to biologic therapy after 1 year. Fourteen patients discontinued biologic therapies due to adverse events. Retention rates were 92.9% at 1 year, 85.5% at 2 years, 78.4% at 3 years and 68.1% at 4 years of treatment. Among all JIA subtypes, only concomitant therapy with corticosteroids was found to be univariately associated with withdrawal of biologic treatment (P = 0.016).Conclusion. Biologic therapies seem effective and safe in patients with JIA. In addition, the retention rates for the first biologic agent are high throughout 4 years.engjournal article10.1093/rheumatology/kev398