Children with juvenile idiopathic arthritis (JIA) treated with subcutaneous golimumab (GLM) showed a rapid response during the initial 16 weeks of treatment, which resulted in inactive disease in 34% of the patients. Despite this response, at week 48, there was no difference in flare rate between patients who continued on GLM and those randomized to placebo.

Hermine I. Brunner, MD, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA, presented the 48-week results of the Study of the Safety and Efficacy of CNTO 148 (Golimumab) in Children With Juvenile Idiopathic Arthritis (JIA) and Multiple Joint Involvement Who Have Poor Response to Methotrexate [GO KIDS; NCT01230827].

The multicenter, double-blind, randomized-withdrawal phase 3 trial involved 2 parts. In the first part, 173 children with JIA received GLM 30 mg/m² every 4 weeks with methotrexate (MTX) until week 16. In part 2, children who achieved clinical response at week 16 were randomized to placebo or continued GLM from week 16 to week 48, with GLM given to patients in the placebo group on flare.

Patients included in this analysis were children aged 2 to 17 years with JIA, active arthritis involving ≥ 5 joints despite > 3 months of MTX at 10 to 30 mg/m², disease duration of ≥ 6 months, and prior exposure to one anti-tumor necrosis factor drug or background therapy with a stable dose of prednisone.

Patients were excluded if they had current or prior uveitis, latent or active tuberculosis or other chronic infection, a history of severe progressive or uncontrolled liver or renal insufficiency (or significant other organ involvement), or a history of or current malignancy.

The primary end point of the study was the proportion of treatment responders at week 16 who did not display flare-up to week 48. Among the secondary end points was the proportion of patients with inactive disease status in part 2.

For part 1, the study found that 151 of 173 (87.3%) children achieved a 30% improvement from baseline in 3 of 6 criteria. Overall, 34.3% of children displayed inactive disease status at the end of part 1 of the study.

However, the study failed to reach its primary end point because no difference was found in flares at week 48 between patients randomized to placebo and those given GLM (52.6% vs 59.0%; P = .414). The study also found no difference in patients with inactive disease from weeks 16 through 48 between GLM and placebo.

On secondary analysis, the study found that only patients with elevated baseline C-reactive protein level had a higher chance of flaring at week 48. However, baseline CRP levels did not influence the response rates to GLM.

In conclusion, the study failed to meet the primary end point as a result of differences in flare rate between the GLM and placebo arms in part 2 of the study. Because of these negative findings, Dr Brunner said that the development program for GLM in JIA has been discontinued.