| A. Patient characteristics | ||
|---|---|---|
| No. of patients | 108 | |
| No. of serum samples | 313 | |
| ATI, n (%) | 26 (8.3) | |
| Age (y), median (IQR) | 42 (18–79) | |
| Weight (kg), median (IQR) | 70 (55–82) | |
| Female, n (%) | 51 (48,6) | |
| IBD type | CD, n (%) | 84 (77.8) |
| UC, n (%) | 24 (22.2) | |
| Albumin (g dL−1), median (IQR) | 4.4 (4.1–4.9) | |
| C‐reactive protein (mg dL−1), median (IQR) | 0.40 (0,10–0.95) | |
| FCP (mg kg−1), median (IQR) | 125 (20–580) | |
| B. Pharmacokinetic parameters estimated and validation | ||
|---|---|---|
| Parameters |
Final Model Estimate (%RSE) |
Bootstrap (n = 1000) Mean (95% CI) |
| CL (L h−1) | 0.0158 (6%) | 0.0159 (0.0141–0.176) |
| Vc (L) | 4.8 (15%) | 4.9 (3.3–6.2) |
| Vp (L) | 4.13* | ‐‐ |
| Q (L h−1) | 0.30* | ‐‐ |
| ATI‐CL | 4.24 (7%) | 4.02 (1.71–7.56) |
| WGT‐CL | 0.177 (34%) | 0.182 (0.03–0.388) |
| FCP‐CL | 0.0175 (28%) | 0.0178 (0.0080–0.0269) |
| IIV‐CL (CV, %) | 22.8 (9%) | 22.6 (19.1–25.9) |
| RUV (CV, %) | 34.1 (11%) | 33.6 (30.7–37.0) |
CLi = CL * (WGT/70) WGT‐CL * (FCP/125) FCP‐CL * ATI‐CL ATI
If detectable anti‐infliximab antibodies, ATI‐CL = 1, else ATI‐CL = 0.
*
Fixed parameters according Fasanmade et al., 2009.
ATI: anti‐infliximab antibody; CD: Crohn's disease; CI: confidence interval; CL: clearance; CV: coefficient of variation; FCP: faecal calprotectin (mg kg−1); IBD: inflammatory bowel disease; IQR: interquartile range; IIV‐CL: interindividual variability on clearance; Q: intercompartment clearance; RSE: residual standard error; RUV: residual unexplained variability; UC: ulcerative colitis; Vc: central volume of distribution; Vp: peripheral volume of distribution; WGT: body weight (kg).