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Background: Biologic disease-modifying anti-rheumatic drugs (bDMARDs) are effective therapies in the treatment of pediatric patients with juvenile idiopathic arthritis (JIA). Upadacitinib (UPA) is an oral selectiveJanus kinase (JAK) inhibitor that primarily targets JAK1, inhibiting the intracellular JAK/Signal Transducers and Activators of Transcription (STAT) [1].To date, it has been approved for the treatment of adults with moderate-to-severe rheumatoid arthritis, spondylarthritis, psoriatic arthritis, to date,as well as adolescents aged 12 years and older with moderate-to-severe atopic dermatitis [2, 3, 4, 5].Clinical experience with UPA and the evaluation of its efficacy in pediatric JIA remains limited, and its use in pediatric cases is still under investigation [6].
Objectives: To evaluate the efficacy of upadacitinib in patients with refractory polyarticularJIA.
Methods: This retrospective case series included 7 patients who were started on upadacitinib therapyata tertiary pediatric rheumatology referral center. All patients receivedoral upadacitinibat a dose of15 mg tablet oncedaily. Demographic data, laboratory findings and previous treatment histories were recorded. Disease activity was assessed at each visit using the Juvenile Arthritis Disease Activity Score in 27 joints (JADAS27 scores).
Results: Of seven pediatric patients,six (85.7 %) were female. The demographic and clinical characteristics of the patients are summarized in Table 1. The mean age atJIAdiagnosis was 11.7±1.7 years, with a mean follow-up duration of58.8±26.3 months. The mean age at initiation of thefirst biologic agent was 12.63±1.9 years. All patients had negative for anti-nuclear antibodies (ANA) and HLA-B27. Two patients (Patient 1 and 6) were positive for rheumatoid factor (RF). All patients had a history of an inadequate response to at least one conventional disease-modifying antirheumatic drug (cDMARD) and were subsequently started on biologic therapy. Each patient had previously experienced treatment failure with at least two anti-tumor necrosis factor (anti-TNF) therapies and either anti-interleukin-6 (tocilizumab) or anti-interleukin-17A (secukinumab) therapy. The mean age at initiation of UPA treatment was 16.1± 1.3 years, and the mean duration of UPA treatment was 8±2.9 months. JADAS27 scores were evaluated before initiation, at 3months, at 6 months and at the last follow up visit during UPA therapy. The mean JADAS27 score before UPA initiation was 20.8 ± 6.4(minimum (min) –maximum (max),11-29.7). After 3 months of treatment, the mean score decreased to 13.14± 4.7(min-max,5.8-21). Excluding four patients (Patients 2 and 4 due to discontinuation and Patients 6 and 7 who received the drug for only 3 months), the mean JADAS27 score decreased further to 2.3 (min-max, 1-3) by the last visit of UPA treatment. However, the mean JADAS27 score of Patients 2 and 4 was 20.75 ±0.35 (min-max, 20.5-21) at their last visit of UPA, indicating that they did not achieve remission. Patient 2 switched to etanercept after 13 months, while Patient 4 transitioned to abatacept therapy after four months of UPA treatment.Among the remaining patients, Patient 1 achieved complete response, while five patients achieved partial responses In patients who responded to UPA treatment, reductions in pain levels and morning stiffness were observed,leading to improved overall comfort and daily functioning. Additionally, a decrease in the number of active joints was documented, reflecting better disease control. None of the patients experienced any adverse reactions during UPA therapy. Notably, none of the patients had a prior diagnosis of uveitis, and no cases of uveitis developed during their follow-up period. Patients reported no difficulties adhering to the oral UPA treatment regimen, with full medication compliance observed throughout the follow-up duration.
Conclusion: This study highlights the promising efficacy of upadacitinib in refractory polyarticular JIA.However,further research, including larger randomized controlled trials, is required to confirm these findings and evaluate the long-term safety profile of this treatment.
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Acknowledgements: NIL.
Disclosure of Interests: None declared.
© The Authors 2025. This abstract is an open access article published in Annals of Rheumatic Diseases under the CC BY-NC-ND license (