Interleukin-1R antagonist (anakinra) induces disease remission in about 50% of corticosteroid (CS) resistant cases of systemic onset JIA (SOJIA) [1, 2]. Clinicians debate whether etanercept should still be tried first before giving anakinra to such patients. Another, more chalenging, issue is to start anakinra even in CS naïve SOJIA patients. We here report our first experiences of such an approach in 7 patients with SOJIA. Four patients had recent onset SOJIA (3 weeks to 3 months) with classical spiking fever, exanthema and arthritis, 3 had a recent flare. They were all treated with indomethacin for at least 2 weeks without effect. There were no signs of haemophagocytosis. Anakinra was started (2 mg/kg sc daily) as an in-patient procedure to monitor for disease progression. Disease activity was monitored at 0, 24, 72 hr and 3 weeks.

Fever and exanthema disappeared within 24 hours, arthritis within 3 days. One child had a recurrence of arthritis without fever or exanthema after 2 weeks. The mean values at t = 72 hrs: CRP decreased from 178 to 33, ESR from 120 to 94, ferritin from 1260 to 375. In 3 of 5 tested NK cell function restored within 72 hr.

Current follow up of 3 weeks anakinra showed persistent remission in 6/7 without the use of CS.

Based on these short term results we would like to propose a RCT (PRINTO?) to define the place of anakinra with a read-out of disease activity and prednisone use.