<h3>Background:</h3> National and international guidelines call for rapid and effective therapy with the aim of achieving an inflammation-free clinical condition as quickly as possible. Nevertheless, the prognosis of many patients remains uncertain, so that an optimisation of the care situation appears necessary. <h3>Objectives:</h3> Improvement and harmonisation of diagnosis, monitoring, treatment decision and prognosis is the aim of the PROKIND protocols [1]. <h3>Methods:</h3> Prospective treat-to-target observational study of patients with polyarticular JIA during the first year of treatment according to the PROKIND recommendations [1]. Acceptability and outcomes of different treatment pathways with treat-to-target strategy for polyarticular JIA are investigated in the GBA-funded project. Patients with initial therapy with methotrexate form cohort 1, patients with additional repeated intravenous corticosteroid pulse therapy form cohort 2, patients with concomitant intra-articular corticosteroid application in at least 5 joints or multiply repeated injections form cohort 3. According to the step up T2T protocol, biologics are added if targets were not reached [1]. <h3>Results:</h3> 160 pJIA patients (RF+ polyarthritis n=24, RF- polyarthritis n=138, unknown RF status n=8) from 23 paediatric rheumatology institutions in Germany and Austria were recruited, 86/53/31 patients were assigned to cohort 1/2/3. Patients of cohort 2 had higher disease activity (JADAs10), higher functional limitations (CHADQ-DI) and higher CRP and ESR (Table 1). The mean JADAS10 showed a decrease in disease activity from 19.2±7.7 at baseline to 3.5±4.6 at month 12, the decrease in CHAQ-DI from 0.9±0.8 to 0.3±0.5 showed improvement in functional capacity. Similarly, improvements in quality of life, pain and fatique were demonstrable. JADAS-inactive disease was achieved by 20.8% at month 3, 42.1% at month 6 and 57.7% at month 12. Escalation to biologic-based therapy was received by 40/86 (47%) of patients in cohort 1 (MTX only), 25/53 (47%) in cohort 2 (MTX+steroid pulses), and 14/31 (45%) in cohort 3 (MTX+extensive i.a. steroids).Treatment escalation to second biologic was used in 10%/9%/10%. Finally, in cohort 1/2/3. A total of 60.4%/48.5% and 66.7.2% had a JADAS inactive disease (JADAS10≤ 2.7) and an additional 25.0%/24.2%/20.8% had a minimal disease activity (JADAS 10 2.8-≤6) and 14.6%/24.2%/12.5 had residual moderate disease activity (JADAS10 6.1-≤17) while only 1 had high disease activity. <h3>Conclusion:</h3> A treat-to-target approach achieves dramatic improvement in disease activity in polyarticular juvenile idiopathic arthritis. Already after 12 months, in about two thirds of patients inactive disease was achieved with marked improvement in functional limitations and quality of life. However, an additional benefit of repeated steroid pulse therapy or extensive intra-articular steroid injections was not recognizable. Due to the study design data must be interpreted with caution. <h3>REFERENCES:</h3> [1] Horneff G, Klein A, Ganser G, Sailer-Höck M, Günther A, Foeldvari I, Weller-Heinemann F. Protocols on classification, monitoring and therapy in children's rheumatology (PROKIND): results of the working group Polyarticular juvenile idiopathic arthritis. Pediatr Rheumatol Online J. 2017 Nov 7;15(1):78. doi: 10.1186/s12969-017-0206-9. PMID: 29116003; PMCID: PMC5678777. <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> <b>None declared.</b>

OP0211 TREAT-TO-TARGET IN POLYARTICULAR JUVENILE IDIOPATHIC ARTHRITIS - A PROTOCOLS IN PAEDIATRIC RHEUMATOLOGY (PROKIND) STUDY