Infliximab levels measured 4 weeks after the first infusion with respect to the development of antibodies to infliximab (ATIs; highest ATI ever measured) during follow-up
| ATI formation during follow-up | Mean (SD) IFX levels 4 weeks after first infusion (μg/ml) | Median (IQR) IFX levels 4 weeks after first infusion (μg/ml) |
|---|---|---|
| ATI, antibody to infliximab; IFX, infliximab; IQR, interquartile range. | ||
| ATI-negative | 12.02 (9.63) | 10.05 (5.40–14.70) |
| ATI <8 μg/ml | 13.22 (7.00) | 12.26 (8.15–21.00) |
| ATI 8–20 μg/ml | 7.34 (6.00) | 7.20 (2.49–10.35) |
| ATI ⩾20 μg/ml | 7.05 (6.13) | 6.08 (1.18–12.15) |
| Inconclusive ATIs | 14.78 (7.66) | 15.65 (9.93–21.00) |