RARE DISEASE
Polyarticular juvenile idiopathic arthritis
Polyarticular juvenile idiopathic arthritis
Polyarticular juvenile idiopathic arthritis
Synonyms: Juvenile polyarthritis, Juvenile polyarticular arthritis, Polyarticular JIA
Synonyms: Juvenile polyarthritis, Juvenile polyarticular arthritis, Polyarticular JIA
Synonyms: Juvenile polyarthritis, Juvenile polyarticular arthritis, Polyarticular JIA
Drug discovery
3
drugs
With orphan designations
Overview
Polyarticular juvenile idiopathic arthritis (pJIA) is a chronic inflammatory arthritis affecting ≥5 joints within the first 6 months of disease onset in children <16 years, characterized by persistent synovitis, joint damage risk, and potential extra-articular complications such as uveitis [1][9][16]. It is subdivided into rheumatoid factor (RF)-positive and RF-negative subtypes, with the former demonstrating similarities to adult rheumatoid arthritis [1][9]. Early diagnosis and aggressive treatment are critical to prevent irreversible joint destruction and disability [3][15].
Population
Therapies
First-line: Methotrexate (subcutaneous preferred) ± intra-articular corticosteroids [3][15]
Biologic escalation: TNF-α inhibitors (etanercept, infliximab) or IL-6 inhibitors for inadequate response [3][7][11]
Early aggressive therapy: Combination DMARD/biologic regimens improve remission rates (40-70% inactive disease at 12-24 months) [3][15]
Categories: rare respiratory diseases, rare systemic and rheumatological diseases, rare systemic or rheumatologic diseases of childhood, rare transplant-related disorders
Research Papers
699 drug discovery papers about Polyarticular juvenile idiopathic arthritis, with 1 first-in-class and 3 next-in-class emerging drug candidates forecasted to outperform the average preclinical success rate. Recent publications:
699 drug discovery papers about Polyarticular juvenile idiopathic arthritis, with 1 first-in-class and 3 next-in-class emerging drug candidates forecasted to outperform the average preclinical success rate. Recent publications:
2026-08-12 | Case Report: Telitacicept in the treatment of refractory juvenile idiopathic arthritis: clinical experience from three cases.
Refractory juvenile idiopathic arthritis (JIA) remains difficult to manage, particularly in patients with persistent disease activity despite multiple conventional synthetic disease-modifying antirheumatic drugs and biologic agents. Telitacicept is a dual inhibitor of B-cell activating factor and a proliferation-inducing ligand, but its use in JIA has not been well described. We report three pediatric patients with refractory JIA treated with telitacicept. Case 1 was a 6-year-old girl with extended oligoarticular JIA who presented with recurrent swelling, pain, and limited motion of multiple joints, and elevated inflammatory markers after previous treatment with methotrexate, leflunomide, adalimumab, and intra-articular glucocorticoids. After switching to telitacicept combined with tofacitinib and methotrexate, joint symptoms and inflammatory markers improved, and an ACR70 response was achieved; clinical improvement was maintained during 12 months of follow-up. Case 2 was a 17-year-old boy with RF-positive polyarticular JIA and long-standing active disease involving the wrists and small joints of the hands. After telitacicept was added to background therapy, joint swelling resolved, inflammatory markers normalized, and ACR90 response was achieved during 9 months of follow-up. Case 3 was an 11-year-old boy with systemic JIA whose systemic manifestations had been controlled but who continued to have predominant polyarticular involvement. After telitacicept initiation, wrist swelling and inflammatory markers improved during the first 2 months, and an early ACR90 response was observed; however, relapse occurred at month 3 with recurrence of systemic symptoms, leading to discontinuation of telitacicept. No serious adverse events were observed. One patient developed a mild upper respiratory tract infection that resolved with symptomatic treatment. These cases provide preliminary clinical observations on telitacicept use in refractory JIA. BAFF/APRIL inhibition may warrant further investigation in selected patients with refractory JIA, particularly those with persistent articular involvement; however, prospective controlled studies are needed to evaluate efficacy and safety.
2026-07-31 | Comprehensive Rehabilitation in Polyarticular Juvenile Idiopathic Arthritis: Functional Recovery in an Adolescent: A Case Report
Background: During a crucial stage of development, juvenile idiopathic arthritis (JIA) can result in chronic pain, stiffness, decreased mobility, and participation restrictions. When pharmaceutical treatment is not enough to restore function, rehabilitation is required. Case Presentation: A 15-year-old kid with rheumatoid factor-positive polyarticular JIA complained of pain and restricted movement in his right ankle, left knee, and both hands. The patient had stopped going to school, needed help with several everyday tasks, and had trouble walking. VAS discomfort of 6/10, CHAQ of 2/3, Barthel Index of 80/100, PedsQL problem score of 59/100, and a 6-minute walk test distance of 228 m were among the initial findings. Rehabilitation Intervention: The four-month multidisciplinary program consists of low-impact endurance exercises, range-of-motion exercises within pain limits, progressive strengthening, occupational therapy for hand function and self-care, paraffin baths, low-level laser therapy, joint protection education, and a home exercise regimen overseen by a carer. Outcome: VAS decreased from 6 to 0–2, CHAQ decreased from 2 to 0.125, and the 6-minute walk test distance increased from 228 to 448 meters at serial evaluations conducted at weeks 4, 9, 14, and 18. The BMI rose from 17.1 to 19.7 kg/m². The patient was able to walk, take care of themselves, and participate in school activities on their own once more. There were no negative effects linked to the treatment. Conclusion: Adolescents with polyarticular JIA who get individual rehabilitation in addition to continued medical therapy report significant clinical improvements in pain, disability, endurance, and participation.
2026-07-10 | Therapeutic efficacy of upadacitinib in refractory juvenile idiopathic arthritis: a case report
Background Juvenile idiopathic arthritis (JIA) remains a clinical challenge when conventional and biological therapies fail. Case presentation This report describes a case of highly refractory JIA and evaluates the efficacy of the Janus kinase (JAK) inhibitor upadacitinib, providing a potential therapeutic reference for difficult-to-treat pediatric autoimmune diseases. A 16-year-old female presented with a 3-year history of polyarticular swelling and pain that worsened over 1 month. Physical examination revealed extensive tenderness in the small joints of the hands, feet, and knees. Functional impairment was noted in the shoulder joints (restricted abduction and lifting) and wrist joints (limited flexion and extension). Laboratory results showed an erythrocyte sedimentation rate of 26 mm/h and a C-reactive protein level of 18.39 mg/L. Musculoskeletal ultrasound indicated grade 1 synovitis with effusion in the bilateral metacarpophalangeal, proximal interphalangeal, and distal interphalangeal joints, as well as both wrist joints. Effusion was also observed in the suprapatellar bursae of both knees. The patient's condition was classified as refractory, with prior failure of multiple lines of therapy, including conventional synthetic disease-modifying antirheumatic drugs (csDMARDs), various biologic DMARDs (bDMARDs) (such as TNF, IL-6, and IL-1 inhibitors), and targeted synthetic DMARDs, such as tofacitinib. Following initiation of upadacitinib, the patient achieved marked clinical remission and improved joint mobility. Conclusions Upadacitinib demonstrated potent efficacy in a pediatric patient with JIA who was nonresponsive to multiple bDMARDs and tofacitinib. These findings suggest that upadacitinib may be a viable salvage therapy for refractory JIA.
2026-04-14 | [Clinical characteristics and outcomes of children with rheu-matoid factor-positive polyarticular juvenile idiopathic arthritis].
To compare the clinical characteristics and outcomes between patients with rheumatoid factor (RF)-positive and RF-negative polyarticular juvenile idiopathic arthritis (pJIA). A retrospective analysis was conducted on clinical data of 131 children diagnosed with pJIA at the Children's Hospital, Zhejiang University School of Medicine from January 2019 to January 2025. Patients were divided into an RF-positive group (n=59) and an RF-negative group (n=72) based on serum RF status. Disease activity was assessed using the Juvenile Arthritis Disease Activity Score-27 (JADAS-27). All patients were followed for at least 6 months, with a maximum follow-up duration of 6 years. Clinical features, laboratory findings, and outcomes were compared between the two groups. Among the 131 pJIA patients, 122 (93.1%) had high disease activity at baseline. Compared with the RF-negative group, the RF-positive group had a higher proportion of females (58.3% vs. 84.7%, P<0.01), an older age at onset (7.14±3.98 years vs. 8.86±4.02 years, P<0.05), and a higher prevalence of interstitial lung disease (4.2% vs. 23.7%, P<0.01). The most frequently affected joints were the wrist in the RF-positive group, and the knee joints in the RF-negative group. At baseline, serum levels of IL-2, IL-6, IL-10, and tumor necrosis factor-α were significantly higher in the RF-positive group than those in the RF-negative group (all P<0.05). A total of 101 patients (77.1%) received biologic-targeted therapies, 46 (78.0%) in RF-positive group, and 55 (76.4%) in RF-negative group. Among them, 23 RF-positive patients (50.0%) and 12 RF-negative patients (21.8%) required two or more biologic-targeted drugs. RF positivity was identified as an independent risk factor for the use of two or more biologic-targeted drugs (OR=3.232, 95%CI: 1.109-9.421, P<0.05). Both groups showed significant reductions in JADAS-27 scores at 3, 6, 12, 24, 36, 48, 60, 72 months after treatment initiation compared with baseline (all P<0.01), with no significant differences in JADAS-27 scores or remission rates between the two groups at any follow-up time point (all P>0.05). The median time to achieve first clinical remission after treatment was 24 months in both groups (P>0.05). No significant differences were observed in remission rates or the proportion of patients requiring two or more biologic-targeted drugs among different types of biologic-targeted drugs (all P>0.05). Children with RF-positive pJIA showed higher baseline inflammatory status and a higher incidence of pulmonary involvement, yet they achieved comparable remission rates to those with RF-negative pJIA. Biologic-targeted therapies may contribute to improved remission rates and outcomes, but RF-positive patients may require switching or combination therapy with different targets to achieve clinical remission.
2026-04-01 | Management of Polyarticular Course Juvenile Idiopathic Arthritis and Temporomandibular Joint Arthritis: A Systematic Literature Review and Meta‐Analysis Informing the APLAR Consensus Recommendations
INTRODUCTION: Juvenile idiopathic arthritis (JIA) is one of the most common chronic rheumatic diseases and requires coordinated and targeted treatment strategies to avoid long-term disability. Existing guidelines from Western countries may not address region-specific factors, including genetic heterogeneity, limited treatment availability, and limitations in healthcare infrastructure, in the Asia Pacific region. The aim of this systematic literature review (SLR) and meta-analysis was to provide up-to-date evidence for the Asia Pacific League of Associations for Rheumatology (APLAR) recommendations for managing polyarticular course JIA (pcJIA) and temporomandibular joint (TMJ) arthritis. METHODS: This systematic review followed PRISMA guidelines, with searches conducted on MEDLINE, Embase, Web of Science, Scopus, and CENTRAL through January 2025. Included studies addressed pharmacologic or non-pharmacologic treatments for pcJIA and TMJ involvement. Studies were limited to publications not already covered in existing guidelines. The Cochrane Rob2 tool and GRADE approach were used to assess quality and evidence certainty. Meta-analyses were performed where applicable. RESULTS: Of the initial 9424 records, 86 studies were included in the qualitative analysis. Methotrexate remains the csDMARD of choice, and subcutaneous administration may be more advantageous. Biological DMARDs, particularly abatacept and tocilizumab, have evidence for good efficacy and acceptable safety profiles. Emerging evidence supports the use of JAK inhibitors. Biosimilars were reported to have efficacy and safety comparable to those of originator biologics in observational studies. Limited evidence suggests that gradual medication tapering after achieving inactive disease status reduces the risk of flares. Evidence for physiotherapy, occupational therapy, and complementary medicine was of very low certainty due to methodological heterogeneity. CONCLUSION: This SLR offers new evidence to support region-specific clinical practice in JIA. While many findings support global recommendations, important evidence gaps remain, particularly in tapering, biosimilar use, TMJ management, and non-pharmacological therapies. These insights will directly inform APLAR's upcoming clinical practice guideline for pcJIA and TMJ arthritis.
2026-08-12 | Case Report: Telitacicept in the treatment of refractory juvenile idiopathic arthritis: clinical experience from three cases.
Refractory juvenile idiopathic arthritis (JIA) remains difficult to manage, particularly in patients with persistent disease activity despite multiple conventional synthetic disease-modifying antirheumatic drugs and biologic agents. Telitacicept is a dual inhibitor of B-cell activating factor and a proliferation-inducing ligand, but its use in JIA has not been well described. We report three pediatric patients with refractory JIA treated with telitacicept. Case 1 was a 6-year-old girl with extended oligoarticular JIA who presented with recurrent swelling, pain, and limited motion of multiple joints, and elevated inflammatory markers after previous treatment with methotrexate, leflunomide, adalimumab, and intra-articular glucocorticoids. After switching to telitacicept combined with tofacitinib and methotrexate, joint symptoms and inflammatory markers improved, and an ACR70 response was achieved; clinical improvement was maintained during 12 months of follow-up. Case 2 was a 17-year-old boy with RF-positive polyarticular JIA and long-standing active disease involving the wrists and small joints of the hands. After telitacicept was added to background therapy, joint swelling resolved, inflammatory markers normalized, and ACR90 response was achieved during 9 months of follow-up. Case 3 was an 11-year-old boy with systemic JIA whose systemic manifestations had been controlled but who continued to have predominant polyarticular involvement. After telitacicept initiation, wrist swelling and inflammatory markers improved during the first 2 months, and an early ACR90 response was observed; however, relapse occurred at month 3 with recurrence of systemic symptoms, leading to discontinuation of telitacicept. No serious adverse events were observed. One patient developed a mild upper respiratory tract infection that resolved with symptomatic treatment. These cases provide preliminary clinical observations on telitacicept use in refractory JIA. BAFF/APRIL inhibition may warrant further investigation in selected patients with refractory JIA, particularly those with persistent articular involvement; however, prospective controlled studies are needed to evaluate efficacy and safety.
2026-07-31 | Comprehensive Rehabilitation in Polyarticular Juvenile Idiopathic Arthritis: Functional Recovery in an Adolescent: A Case Report
Background: During a crucial stage of development, juvenile idiopathic arthritis (JIA) can result in chronic pain, stiffness, decreased mobility, and participation restrictions. When pharmaceutical treatment is not enough to restore function, rehabilitation is required. Case Presentation: A 15-year-old kid with rheumatoid factor-positive polyarticular JIA complained of pain and restricted movement in his right ankle, left knee, and both hands. The patient had stopped going to school, needed help with several everyday tasks, and had trouble walking. VAS discomfort of 6/10, CHAQ of 2/3, Barthel Index of 80/100, PedsQL problem score of 59/100, and a 6-minute walk test distance of 228 m were among the initial findings. Rehabilitation Intervention: The four-month multidisciplinary program consists of low-impact endurance exercises, range-of-motion exercises within pain limits, progressive strengthening, occupational therapy for hand function and self-care, paraffin baths, low-level laser therapy, joint protection education, and a home exercise regimen overseen by a carer. Outcome: VAS decreased from 6 to 0–2, CHAQ decreased from 2 to 0.125, and the 6-minute walk test distance increased from 228 to 448 meters at serial evaluations conducted at weeks 4, 9, 14, and 18. The BMI rose from 17.1 to 19.7 kg/m². The patient was able to walk, take care of themselves, and participate in school activities on their own once more. There were no negative effects linked to the treatment. Conclusion: Adolescents with polyarticular JIA who get individual rehabilitation in addition to continued medical therapy report significant clinical improvements in pain, disability, endurance, and participation.
2026-07-10 | Therapeutic efficacy of upadacitinib in refractory juvenile idiopathic arthritis: a case report
Background Juvenile idiopathic arthritis (JIA) remains a clinical challenge when conventional and biological therapies fail. Case presentation This report describes a case of highly refractory JIA and evaluates the efficacy of the Janus kinase (JAK) inhibitor upadacitinib, providing a potential therapeutic reference for difficult-to-treat pediatric autoimmune diseases. A 16-year-old female presented with a 3-year history of polyarticular swelling and pain that worsened over 1 month. Physical examination revealed extensive tenderness in the small joints of the hands, feet, and knees. Functional impairment was noted in the shoulder joints (restricted abduction and lifting) and wrist joints (limited flexion and extension). Laboratory results showed an erythrocyte sedimentation rate of 26 mm/h and a C-reactive protein level of 18.39 mg/L. Musculoskeletal ultrasound indicated grade 1 synovitis with effusion in the bilateral metacarpophalangeal, proximal interphalangeal, and distal interphalangeal joints, as well as both wrist joints. Effusion was also observed in the suprapatellar bursae of both knees. The patient's condition was classified as refractory, with prior failure of multiple lines of therapy, including conventional synthetic disease-modifying antirheumatic drugs (csDMARDs), various biologic DMARDs (bDMARDs) (such as TNF, IL-6, and IL-1 inhibitors), and targeted synthetic DMARDs, such as tofacitinib. Following initiation of upadacitinib, the patient achieved marked clinical remission and improved joint mobility. Conclusions Upadacitinib demonstrated potent efficacy in a pediatric patient with JIA who was nonresponsive to multiple bDMARDs and tofacitinib. These findings suggest that upadacitinib may be a viable salvage therapy for refractory JIA.
2026-04-14 | [Clinical characteristics and outcomes of children with rheu-matoid factor-positive polyarticular juvenile idiopathic arthritis].
To compare the clinical characteristics and outcomes between patients with rheumatoid factor (RF)-positive and RF-negative polyarticular juvenile idiopathic arthritis (pJIA). A retrospective analysis was conducted on clinical data of 131 children diagnosed with pJIA at the Children's Hospital, Zhejiang University School of Medicine from January 2019 to January 2025. Patients were divided into an RF-positive group (n=59) and an RF-negative group (n=72) based on serum RF status. Disease activity was assessed using the Juvenile Arthritis Disease Activity Score-27 (JADAS-27). All patients were followed for at least 6 months, with a maximum follow-up duration of 6 years. Clinical features, laboratory findings, and outcomes were compared between the two groups. Among the 131 pJIA patients, 122 (93.1%) had high disease activity at baseline. Compared with the RF-negative group, the RF-positive group had a higher proportion of females (58.3% vs. 84.7%, P<0.01), an older age at onset (7.14±3.98 years vs. 8.86±4.02 years, P<0.05), and a higher prevalence of interstitial lung disease (4.2% vs. 23.7%, P<0.01). The most frequently affected joints were the wrist in the RF-positive group, and the knee joints in the RF-negative group. At baseline, serum levels of IL-2, IL-6, IL-10, and tumor necrosis factor-α were significantly higher in the RF-positive group than those in the RF-negative group (all P<0.05). A total of 101 patients (77.1%) received biologic-targeted therapies, 46 (78.0%) in RF-positive group, and 55 (76.4%) in RF-negative group. Among them, 23 RF-positive patients (50.0%) and 12 RF-negative patients (21.8%) required two or more biologic-targeted drugs. RF positivity was identified as an independent risk factor for the use of two or more biologic-targeted drugs (OR=3.232, 95%CI: 1.109-9.421, P<0.05). Both groups showed significant reductions in JADAS-27 scores at 3, 6, 12, 24, 36, 48, 60, 72 months after treatment initiation compared with baseline (all P<0.01), with no significant differences in JADAS-27 scores or remission rates between the two groups at any follow-up time point (all P>0.05). The median time to achieve first clinical remission after treatment was 24 months in both groups (P>0.05). No significant differences were observed in remission rates or the proportion of patients requiring two or more biologic-targeted drugs among different types of biologic-targeted drugs (all P>0.05). Children with RF-positive pJIA showed higher baseline inflammatory status and a higher incidence of pulmonary involvement, yet they achieved comparable remission rates to those with RF-negative pJIA. Biologic-targeted therapies may contribute to improved remission rates and outcomes, but RF-positive patients may require switching or combination therapy with different targets to achieve clinical remission.
2026-04-01 | Management of Polyarticular Course Juvenile Idiopathic Arthritis and Temporomandibular Joint Arthritis: A Systematic Literature Review and Meta‐Analysis Informing the APLAR Consensus Recommendations
INTRODUCTION: Juvenile idiopathic arthritis (JIA) is one of the most common chronic rheumatic diseases and requires coordinated and targeted treatment strategies to avoid long-term disability. Existing guidelines from Western countries may not address region-specific factors, including genetic heterogeneity, limited treatment availability, and limitations in healthcare infrastructure, in the Asia Pacific region. The aim of this systematic literature review (SLR) and meta-analysis was to provide up-to-date evidence for the Asia Pacific League of Associations for Rheumatology (APLAR) recommendations for managing polyarticular course JIA (pcJIA) and temporomandibular joint (TMJ) arthritis. METHODS: This systematic review followed PRISMA guidelines, with searches conducted on MEDLINE, Embase, Web of Science, Scopus, and CENTRAL through January 2025. Included studies addressed pharmacologic or non-pharmacologic treatments for pcJIA and TMJ involvement. Studies were limited to publications not already covered in existing guidelines. The Cochrane Rob2 tool and GRADE approach were used to assess quality and evidence certainty. Meta-analyses were performed where applicable. RESULTS: Of the initial 9424 records, 86 studies were included in the qualitative analysis. Methotrexate remains the csDMARD of choice, and subcutaneous administration may be more advantageous. Biological DMARDs, particularly abatacept and tocilizumab, have evidence for good efficacy and acceptable safety profiles. Emerging evidence supports the use of JAK inhibitors. Biosimilars were reported to have efficacy and safety comparable to those of originator biologics in observational studies. Limited evidence suggests that gradual medication tapering after achieving inactive disease status reduces the risk of flares. Evidence for physiotherapy, occupational therapy, and complementary medicine was of very low certainty due to methodological heterogeneity. CONCLUSION: This SLR offers new evidence to support region-specific clinical practice in JIA. While many findings support global recommendations, important evidence gaps remain, particularly in tapering, biosimilar use, TMJ management, and non-pharmacological therapies. These insights will directly inform APLAR's upcoming clinical practice guideline for pcJIA and TMJ arthritis.
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Drug Discovery Landscape
3 orphan drug designations for Polyarticular juvenile idiopathic arthritis, including 3 approved therapies.
3 orphan drug designations for Polyarticular juvenile idiopathic arthritis, including 3 approved therapies.
Drug | Therapy type | Regulator | Orphan designation | Approval | Sponsor |
|---|---|---|---|---|---|
methotrexate oral solution [Xatmep] | small molecules | FDA | 2015-08-27 | 2017-04-25 | Silvergate Pharmaeuticals, Inc. |
golimumab [SIMPONI ARIA®] | antibodies | FDA | 2015-04-02 | 2020-09-29 | Janssen Research & Development, LLC |
tocilizumab [Actemra] | antibodies | FDA | 2012-07-31 | 2013-04-29 | Genentech, Inc. |
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