Clozapine levels and therapeutic response: using individual patient meta-analysis data for a ROC Curve analysis

Introduction Clozapine has been well established as the most efficacious medication for treatment refractory schizophrenia. Optimising benefit during clozapine trial is an important clinical consideration. Therapeutic drug monitoring of plasma or serum levels formed a critical part this. Though there no agreed standardised therapeutic range, advice traditionally recommends level >350ng/mL in order to effect best response. Most studies analysing relationship between response and are older, have small sample sizes, do not consider whether additional factors might assist determining optimal Objectives We conducted systematic review PubMed, PsycInfo Embase that provided individual participant data on Methods This was analysed using Receiver Operating Characteristic (ROC) curves determine prediction performance Results were able include 294 participants. ROC analysis yielded area under curve (AUC) 0.612. The at Youden index 372ng/mL, this sensitivity 57.3%, specificity 65.7%. interquartile range 223ng/mL – 558ng/mL. There improvement with mixed models including patient sex, age length trial. Conclusions dose should be optimised based levels. found 250 550ng/mL could recommended, while noting Disclosure Interest None Declared