OBJECTIVES: To evaluate the safety and efficacy of adalimumab (AD) administration in patients with juvenile idiopathic arthritis (JIA).METHODS: Twenty-six patients were enrolled from January 2004 to January 2008 in this prospective observational study. Inclusion criteria were either unresponsiveness to disease-modifying anti-rheumatic drugs (DMARDs; n = 17) or to other anti-tumour necrosis factor (anti-TNF) agents (n = 9) or development of uveitis under other anti-TNFs (n = 2 of the 9). Efficacy was estimated using the American College of Rheumatology Pediatric (ACR Pedi) criteria.RESULTS: After 1-5 years of AD exposure, nine different adverse events (AEs) were recorded (12.6 AEs/100 patient-years), mainly mild respiratory tract infections and injection site-related reactions. Serious AEs (SAEs, 2.8/100 patient-years) were the development of abscess at the site of injection (n = 1) and lethal sepsis (n = 1). The ACR Pedi ≥ 30 responses for the first to the fifth year of treatment were 88.5, 57.7, 50.0, 34.6, and 11.5%, respectively. In total, 17 of the 26 (65.4%) patients responded to AD. Five of the 11 patients under steroids discontinued them 6 months post-treatment. Seven patients required weekly AD treatment to maintain remission and four of them benefited from this policy. Recurrent uveitis was hindered in three of the six patients, no new cases were recorded, and radiological regression was observed in two of the four patients with lesions.CONCLUSIONS: AD was safe and efficacious during the study period in the majority of patients. However, vigilance is required for the early detection of severe and potentially fatal infections. AD may control recurrent uveitis and radiological progression.