Objective, To evaluate safety and efficacy of high dose etanercept (> 0.8 m
g/kg, maximum 25 mg subcutaneously twice weekly) (Enbrel((R))) in children
with juvenile rheumatoid arthritis (JRA) and inadequate prior response to s
tandard dose etanercept.
Methods, Retrospective chart review of 8 children (6 girls, 2 boys, mean ag
e 8.4 yrs, range 5-16 yrs). Five children had systemic onset, polyarticular
course JRA; 2 had polyarticular onset; and one had pauciarticular onset, p
olyarticular course JRA. All children had failed at least 3 mo (mean 9 mo)
treatment with standard dose etanercept (0.4 mg/kg SC twice a week). All 8
children had increase in the etanercept dose to at least 0.8 mg/kg (mean 1.
1 mg/kg, maximum 25 mg SC twice weekly) for a mean of 7 mo (range 3-10 mo).
Efficacy of high dose etanercept was evaluated by changes in joint count,
laboratory data, and ability to decrease concomitant medication.
Results. Improvements in the joint count and laboratory findings (erythrocy
te sedimentation rate, hemoglobin and platelet count) were observed in 2 of
8 (25%) children. In these 2, concomitant prednisone was reduced or discon
tinued. In contrast, no changes in disease activity or laboratory findings
were observed in the other 6 children. Overall, high dose etanercept was we
ll tolerated. No laboratory abnormalities were detected and no child withdr
ew because of adverse events.
Conclusion. High dose etanercept is safe and well tolerated in children, bu
t efficacy seems limited. In children with unsatisfactory response to stand
ard dose etanercept, an increased dose or treatment prolongation may not of
fer any additional benefit.