Etanercept is well-tolerated and safe for up to 6 years in patients with extended oligoarticular juvenile idiopathic arthritis, psoriatic arthritis and enthesitis-related arthritis, according to data published in Arthritis Research & Therapy.
“Clinical Study In Pediatric Patients of Etanercept for Treatment of ERA, PsA, and Extended Oligoarticular (CLIPPER) was a 2-year open-label study, designed to assess efficacy and safety of [etanercept] in pediatric patients with [extended oligoarticular JIA (eoJIA)], [enthesitis-related arthritis (ERA)] and PsA,” Ivan Foeldvari, MD, of the Hamburg Center for Pediatric and Adolescent Rheumatology in Germany, and colleagues wrote. “CLIPPER and CLIPPER2, its 8-year long-term extension, will provide efficacy and safety data for up to 10years of treatment in this patient population.”
To analyze the safety and efficacy of etanercept (Enbrel, Amgen) in patients with extended oligoarticular JIA, PsA and enthesitis-related arthritis after 6 years, Foeldvari and colleagues reported on data from the 2-year, phase 3 CLIPPER trial as well as the first 4 years of its long-term extension. According to the researchers, patients who completed CLIPPER were permitted to enroll in CLIPPER2, in which children were treated with weekly, 0.8 mg/kg doses etanercept. The maximum allowable dose of 50 mg per week.
Etanercept is well-tolerated and safe for up to 6 years in patients with extended oligoarticular JIA, psoriatic arthritis and enthesitis-related arthritis, according to data.
Among the 127 juveniles initially enrolled in CLIPPER, 109 participated in CLIPPER2. After 4 years in the long-term extension, and a total of 6 years in both studies, 41 participants were still receiving etanercept and 19 discontinued treatment permanently due to withdrawal from the study, loss of follow up, adverse event, insufficient clinical response, protocol violation or pregnancy. In addition, 36 patients ceased treatment for another reason and were still being observed, and 13 had entered the treatment withdrawal phase after achieving low or inactive disease, of whom seven had to restart etanercept.
Foeldvari and colleagues assessed efficacy using the JIA core set of outcomes, the JIA American College of Rheumatology response criteria (JIA-ACR), and the Juvenile Arthritis Disease Activity Score (JADAS). Safety analyses included treatment-emergent adverse events.
According to the researchers, 58% of participants achieved JIA-ACR90, while 48% achieved JIA-ACR100 and 32% had JADAS inactive disease status after the initial 2years of treatment in CLIPPER. Following an additional 4years in CLIPPER2, those figures decreased to 46%, 35% and 24% respectively among patients who remained in the trial.
The most frequently reported treatment-emergent adverse events were headache, with an incidence of 5.3 per 100 patient-years, arthralgia, with an incidence of 4.6 events per 100 patient-years, and pyrexia, which had an incidence of 3.8 per 100 patient-years. The total number of such adverse events, excluding infections and injection site reactions, decreased during the total 6-year period from 193 during year one to 37 in year six. There was one case of malignancy — Hodgkin’s lymphoma — reported, but no cases of active tuberculosis, demyelinating disorders or deaths.
“This is the first report on the safety and efficacy of [etanercept] in patients with eoJIA, ERA or PsA that spans over 6years of continuous treatment,” Foeldvari and colleagues wrote. “The study shows that treatment with [etanercept] is effective, with acceptable safety and tolerability. Disease activity measures and [patient-reported outcomes] were relatively stable from the previously reported results after 2years of treatment to the end of year 6 in the current report, suggesting a long-term maintenance of clinical benefits.” – by Jason Laday
Disclosures: Foeldvari reports advisory board memberships with AbbVie, Novartis, Chugai and Genzyme.