Figure 2 Relationship between EULAR response and presence or absence of anti‐adalimumab antibodies. Of the 11 patients with anti‐adalimumab antibody concentrations above 100 AU/ml, nine (82%) were non‐responders and two (18%) were moderate responders. Of the 10 patients with anti‐adalimumab concentrations of 12–100 AU/ml, only three were non‐responders (30%), five were moderate responders (50%), and two were good responders (20%). Of the 100 patients in whom no antibodies against adalimumab were detected during the 28 weeks follow‐up, 23 were non‐responders, 41 were moderate responders, and 35 were good responders. EULAR non‐responders had anti‐adalimumab antibodies significantly more often than good responders (p = 0.006) and moderate responders (p = 0.039), and most non‐responders were found in the group with high (>100 AU/ml) anti‐adalimumab concentrations compared with the group with low (12–100 AU/ml) anti‐adalimumab concentrations.