The value of old drugs for juvenile idiopathic arthritis

Pharmacological conditioning for juvenile idiopathic arthritis: a potential solution to reduce methotrexate intolerance

BACKGROUND

Methotrexate (MTX) therapy has proven to be a successful and safe treatment for Juvenile Idiopathic Arthritis (JIA). Despite the high efficacy rates of MTX, treatment outcomes are often complicated by burdensome gastro-intestinal side effects. Intolerance rates for MTX in children are high (approximately 50%) and thus far no conclusive effective treatment strategies to control for side effects have been found. To address this need, this article proposes an innovative research approach based on pharmacological conditioning, to reduce MTX intolerance.

PRESENTATION OF THE HYPOTHESIS

A collaboration between medical psychologists, pediatric rheumatologists, pharmacologists and patient groups was set up to develop an innovative research design that may be implemented to study potential improved control of side effects in JIA, by making use of the psychobiological principles of pharmacological conditioning. In pharmacological conditioning designs, learned positive associations from drug therapies (conditioning effects) are integrated in regular treatment regimens to maximize treatment outcomes. Medication regimens with immunosuppressant drugs that made use of pharmacological conditioning principles have been shown to lead to optimized therapeutic effects with reduced drug dosing, which might ultimately cause a reduction in side effects.

TESTING THE HYPOTHESIS

This research design is tailored to serve the needs of the JIA patient group. We developed a research design in collaboration with an interdisciplinary research group consisting of patient representatives, pediatric rheumatologists, pharmacologists, and medical psychologists.

IMPLICATIONS OF THE HYPOTHESIS

Based on previous experimental and clinical findings of pharmacological conditioning with immune responses, we propose that the JIA patient group is particularly suited to benefit from a pharmacological conditioning design. Moreover, findings from this study may potentially also be promising for other patient groups that endure long-lasting drug therapies.

Disease activity and damage in juvenile idiopathic arthritis: methotrexate era versus biologic era

Objective

To compare the long-term disease state, in terms of activity and damage, of children with juvenile idiopathic arthritis (JIA) who had their disease onset in methotrexate (MTX) or biologic eras.

Methods

Patients were included in MTX or biologic era cohort depending on whether their disease presentation occurred before or after January 2000. All patients had disease duration ≥ 5 years and underwent a prospective cross-sectional assessment, which included measurement of disease activity and damage. Inactive disease (ID) and low disease activity (LDA) states were defined according to Wallace, JADAS10, and cJADAS10 criteria. Articular and extraarticular damage was assessed with the Juvenile Arthritis Damage Index (JADI).

Results

MTX and biologic era cohorts included 239 and 269 patients, respectively. Patients were divided in the “functional phenotypes” of oligoarthritis and polyarthritis. At cross-sectional visit, patients in the biologic era cohort with either oligoarthritis or polyarthritis had consistently higher frequencies of ID and LDA by all criteria. The measurement of disease damage at cross-sectional visit revealed that the frequency of impairment of > 1 JADI-Articular items was higher in MTX than in biologic era cohort (17.6% versus 11% in oligoarthritis and 52.6% versus 21.8% in polyarthritis). Likewise, frequency of involvement of > 1 JADI-Extraarticular items was higher in the MTX than in the biologic era cohort (26.5% versus 16.2% in oligoarthritis and 31.4% versus 13.5% in polyarthritis).

Conclusion

Our study provides evidence of the remarkable outcome improvement obtained with the recent therapeutic advance in JIA.

Update on the pathogenesis and treatment of juvenile idiopathic arthritis

PURPOSE OF REVIEW

To provide an overview of recently published studies on pathogenesis and management of juvenile idiopathic arthritis (JIA).

RECENT FINDINGS

In the past year, the potential role of network analysis in the understanding of the molecular phenotype of individual JIA subgroups has been highlighted. In addition, potential new targets for pharmacologic interventions have been identified through the elucidation of mechanisms that modulate the function of cells involved in the inflammatory process. There is a growing interest for the role of the gut microbiome in disease pathogenesis, which may open the way to future therapeutic manipulations of fecal microbial population. Recent therapeutic studies have provided important information in large patient samples on the effectiveness and toxicity profile of biologic medications used in JIA. Concomitant administration of methotrexate was found to increase the effectiveness of intra-articular corticosteroid therapy in children with oligoarticular JIA.

SUMMARY

A great deal of work is being conducted to better define the molecular phenotype of the individual subsets of JIA and to identify potential new targets for therapeutic interventions. The results of the ongoing large-scale international data collections will help establish the long-term safety profiles of biologic medications, in particular the risk of malignancy.