ADA and juvenile idiopathic arthritis: The impactof ADA on serum golimumab concentrations was consistent in JIA and RA studies,whereby higher ADA titres were associated with lower drugconcentrations.28,39,41,56 This was generally shown at ADA titres >1:1000 in JIA,39 and in adults, median peak titres ⩾100 were associated with undetectableor very low drug levels.57 Interestingly, in another study in PsA, which used a standard assay, thegolimumab dose (50 mg versus 100 mg) did not appear to affectthe ADA rates, which remained low for the whole duration of the study through toweek 52 (4.9%).58