Background: Anti-tumor necrosis factor-alpha and anti-integrin monoclonal antibodies
show great benefits for inducing and maintaining remission, healing the mucosa and restoring the
quality of life of patients with inflammatory bowel disease. However, the therapeutic potential of these
intrinsically powerful biologicals is abated by a high variability in response. Some patients experience
no benefit from these treatments, while others lose response over time. Therapeutic Drug Monitoring
(TDM) is a promising tool to further improve therapeutic outcome, substantiated by the finding that
highly variable clinical response is correlated with pharmacokinetic (PK) variability. Serum Trough
Concentrations (TCs) of the drug are measured and dosage regimens are adapted in order to achieve
target TCs that correlate with beneficial therapeutic outcomes. The TC concept is relatively simple but
gives only a partial insight in PK. PK profiles should be interpreted in the light of patient specific influences
(i.e., covariates) that explain variability.
Objective: Therefore, the aim of TDM must be to dose the biological in such a way that a personal optimal
PK profile is achieved. Furthermore, currently used “treat-to-target” algorithms have proven to increase
the therapeutic potential of the drugs, but dosage regimen adaptations are still robust guesswork.
Results: A clinical decision support tool for accurately forecasting drug exposure would significantly
impact TDM and is suggested to promote successful implementation of individualized predictive
treatment in clinical practice.
Conclusion: This review provides a clinician-oriented overview of the state-of-the-art, the gaps in current
knowledge and future potential of individualized predictive treatment.