Juvenile rat and pediatric trazodone studies: how to gain extra sensitivity to overcome bioanalytical challenges.

Trazodone (TZD) is used for the treatment of depression in adults and, off-label, as a sleep medication in adult and pediatric populations. The off-label use is well documented, however further clinical studies are needed to confirm its efficacy and safety for the treatment of sleep disorders. In this scenario, we developed a bioanalytical method to quantify low TZD concentrations in samples collected by capillary microsampling (CMS) to support dose finding, Good Laboratory Practice juvenile rat toxicokinetic and upcoming pediatric studies. A method using only 8 μl of plasma was developed and successfully used for analyzing CMS samples from juvenile rats throughout toxicokinetic study. By harmoniously maximizing each analytical step, we achieved a sensitive method to quantify TZD in CMS samples.