Terapêutica Biotecnológica na Artrite Idiopática Juvenil: Implicações Fisiopatológicas e Terapêutica Dirigida

Abstract

Objective In this retrospective cohort study, we aim to investigate the most used biological DMARDs in JIA patients in a pediatric rheumatologic unit from a Portuguese tertiary hospital, their effectiveness and safety. We also intended to link their effectiveness and the pathophysiology of the disease.

Methods We reviewed medical records of JIA patients exposed to biological DMARDs in pediatric rheumatologic unit from a Portuguese tertiary hospital. We accessed therapy effectiveness based on presence of arthritis, uveitis, rash, fever, splenomegaly, serositis, generalized lymphadenopathy and normal CRP and ESR levels according to Wallace Criteria for inactive disease in JIA. Effectiveness of different bDMARDs in the several JIA subtypes was linked to the disease´s pathophysiology. Adverse effects were also reviewed.

Results Thirty-four patients were included in the study. Overall, nineteen patients (67,9%) had inactive disease at last evaluation. Six patients with missing data on inactive disease status were excluded from this analysis.Number of affected joints, ESR and CRP values were significantly lower at 3, 6, 12 and 24 months after bDMARD therapy. All systemic JIA patients (n=10) were initially treated with Anakinra. Six (60%) attained inactive disease and three (30%) switched to Tocilizumab due to ineffectiveness in the control of articular features. Patients who switched to tocilizumab achieved inactive disease until the end of the follow-up. All patients with the other subtypes of JIA (n=24) were treated with TNF inhibitors. Inactive disease was achieved in 55,6%. Adverse effects occurred in eight patients (23,5%).

Conclusions The results of the present study demonstrate the effectiveness of bDMARs in the study population. bDMARDs reduced the number of affected joints, CRP and ESR values after three months of treatment, and this effectiveness was sustained over the two years of follow-up. For systemic JIA, preferred drug was Anakinra, an IL-1 inhibitor, and its effectiveness was consistent with previous studies. In the other JIA subtypes, TNF inhibitors were the most used bDMARDs, and showed an effectiveness consistent with previous studies. The most used bDMARDs for each JIA subtype are in line with pathophysiological differences. Our results demonstrated the safety of these drugs. All adverse effects found in our study population were previously reported in literature.