A Study to Evaluate Efficacy and Safety of Anakinra in the Treatment of Still's Disease (SJIA and AOSD)

The study consists of a 12-week, randomized, double-blind, placebo controlled period with two dose levels of anakinra and a 4-week safety follow-up after last dose of investigational medicinal product (IMP). The primary endpoint will be evaluated at Week 2. Sustained efficacy and time to study drug discontinuation will be evaluated during the full study period. A screening visit is optional and may be done to identify patients that could be suitable for the study. During the study 6 visits and 2 telephone contacts are scheduled i.e., Day 1 (baseline visit), Day 4Tel, Week 1, Week 2, Week 4, Week 8, Week 12 and Week 16Tel (End of Study). Patients will be randomly assigned to study drug, after they meet all of the inclusion criteria and none of the exclusion criteria. Patients will receive treatment for 12 weeks, either anakinra or placebo. Patients will be randomized to anakinra in a dose of either 2 or 4 mg/kg/day, with a maximum dose of 100 or 200 mg once daily, respectively. Patients will be randomized to placebo with corresponding volumes for each of the two anakinra dose levels.