Background: therapeutic monitoring of anti-TNF drugs and anti-drug antibody levels are useful for clinical decision-making, via the rationalization and optimization of the use of anti-TNF treatments. The objective of the present study was to validate the model of Ternant et al., in a cohort of patients with inflammatory bowel diseases (IBD). This model was originally established for patients with rheumatoid arthritis and was used in this study to optimize the adalimumab (ADA) dose and predict ADA trough levels (ATL).
Methods: this study used concentration data points from 30 IBD patients who received ADA treatment between 2014 and 2015. A goodness-of-fit of the model was determined by evaluating the relationship between the observed ATL values and population model-predicted values (PRED) or individual model-predicted values (IPRED).
Results: a total of 51 ADA concentration points were analyzed. The bias of the model was 2.39 (95% CI, 1.63-3.15) for PRED and 0.63 (95% CI, 0.23-1.03) for IPRED. The precision was 3.57 (95% CI, 2.90-4.13) and 1.53 (95% CI, 1.22-1.80), respectively.
Conclusions: therapeutic drug monitoring involving ATL may allow the optimization of the treatment of IBD patients. The validation results of the phamacokinectic (PK) model for ADA in IBD patients are inadequate. However, additional studies will strengthen the bias and precision of the model.