Background Pediatric patients with a polyarticular course of juvenile idiopathic arthritis (JIA) may not respond sufficiently to methotrexate (MTX) combined with TNF Alpha antagonists (TNFaA). In this cases switching to another TNFaA might be beneficial, although it is recommended to switch to another non-TNFaA biologic. Certolizumab pegol (CZP) consists of a Fab fragment of a pegylated monoclonal TNF Alpha antibody.
Objectives The aim of the retrospective data analysis is to evaluate the efficacy and safety of CZP in children with polyarticular course JIA not sufficiently responsive to other TNFaA (and MTX).
Methods Following the clinical impression of a high efficacy of CZP in pediatric patients with polyarticular course JIA not sufficiently responsive to previous treatment with other TNFaA, our clinical database was searched for patients treated with CZP. All patients were included. Demographic data and joint counts (active joints, AJ; tender joints, TJ; limited joints, LJ; temporomandibular joint, TMJ, abnormalities - pain, limitation, asymmetry) were extracted. According to the TNFaA used during the entire retrospective observational period, different drug groups were formed. Efficacy was evaluated by the changes comparing joint counts at treatment start (t0) and at last available visit (tx) for each TNFaA treatment, which was lasting for at least 3 months. Comparability of t0 joint counts among drug groups was calculated.
The safety analysis consisted in the documentation of adverse drug reactions (ADR).
Results 75 patients (boys:girls=1:3), median age 12 (min 3, max 19) years were identified, where 25 were pre-treated with Etanercept (ETN) and 50 with Adalimumab (ADA) respectively, co-medication with MTX. Three groups were established: ETN, ADA, and CZP. Age, gender and diagnosis distribution as well as all joint counts including the TMJ were comparable at t0 among all 3 groups. At tx, statistically significant (p=0.005 – p<0.0001) changes for all joint counts were reached only for treatment with CZP but not for ETN or ADA. TMJ showed statistically significant (p<0.0001) improvement of abnormalities at tx compared to t0.
Ten patients had uveitis, where 8 did not experience a flare during treatment with CZP. In one patient uveitis was successfully treated with CZP. In another patient CZP was not sufficient to prevent a flare of uveitis.
ADR related to CZP were found in 10 cases: 6 with skin rash, 3 with headaches. The last ADR contained no detailed information about the nature of the event. No serious ADR were found.
Graphic 1: changes in active joint (AJ) count between t0=baseline and tx=last visit. Statistical significant changes were achieved only in the CZP cohort.
Conclusions Despite all limitations to a retrospective data analysis, the results of this study show an overall high efficacy of the treatment with CZP in pediatric patients with polyarticular course JIA not sufficiently responsive to pre-treatment with other TNFaA (and MTX) with an acceptable safety profile.
Disclosure of Interest None declared