Therapeutic drug monitoring (TDM) assays provide information for therapeutic decisions allowing a personalised treatment strategy aimed to maximise patient response whilst minimising overexposure to the therapeutic drug(s).
Use of biologic therapies such as monoclonal antibodies and fusion proteins have changed the clinical course of many autoimmune conditions such as inflammatory bowel disease (IBD) psoriasis and rheumatoid arthritis1. Despite the beneficial responses observed in patients undergoing such therapies with biologics, primary non-response and secondary loss of response (SLR) to these treatments is common, with SLR occurring in approximately 70% of patients1.
Treatment with biologics is expensive and with a limited choice of agents suitable for use in IBD patients, monitoring of the response is key to preventing such loss of response. TDM involves the assessment of drug levels within an individual together with the detection of antibodies against the drug. TDM is typically managed in 2 ways: Proactive and Reactive testing.
Proactive TDM is used in patients demonstrating a response to the specific therapy as a tool to optimise the therapy, potentially to prevent periodic disease flares and loss of response; it helps minimise overexposure to the drug while maximising the patient response. Reactive TDM is performed in patients demonstrating a loss of response, to guide decision making2.
The use of either Proactive or Reactive TDM has been shown to be a cost-effective strategy to reduce the high cost associated with management of chronic inflammatory diseases.
Publications
1. Silva-Ferreira F, Afonso J, Pinto-Lopes P, Magro F. A Systematic Review on Infliximab and Adalimumab Drug Monitoring: Levels, Clinical Outcomes and Assays. Inflamm Bowel Dis. 2016;22(9):2289-2301. doi:10.1097/MIB.0000000000000855
2. Roblin X, Riviere P, Flamant M, et al. Proactive Therapeutic Drug Monitoring of TNF Antagonists in Inflammatory Bowel Disease. Inflamm Bowel Dis. 2018;24(9):1904-1909. doi:10.1093/ibd/izy069
