Therapeutic Drug Monitoring of Brodalumab in Psoriasis Patients (BIOLOPTIM-BRO)

Biologics, such as brodalumab, are currently the most effective treatment option for patients with moderate-to-severe psoriasis. But they are costly for health care systems and prescribed according to a 'one dose fits all' dosing regimen, leading to potential over- and undertreatment. Within this study we aim to investigate the predictive value of early serum trough levels of brodalumab and determine the therapeutic window of brodalumab in psoriasis patients.

Patients will be included after siging informed consent. After inclusion, patients will continue on standard dosing schedule of brodalumab (i.e. one loading dose first (210mg), once a week for 2 weeks (210mg), then a regular dose regimen (210mg) every 2 weeks). During each study visit, blood will be taken in order to quantify Ctroughs and/or anti-drug antibodies towards brodalumab. In addition, the Psoriasis Severity and Area Index (PASI) and the Investigator's Global Assessment (IGA) score will be evaluated by a physician. Patients complete the Dermatology Life Quality Index (DLQI) and European quality of life EQ-5D instrument at each visit.