Capillary Olanzapine Sampling Method validatiOn Study

To ensure adequate exposure to drugs, blood concentration measurements can be
used to optimize drug doses, a practice known as therapeutic drug monitoring
(TDM). Applying TDM for antipsychotic drug users is important to gain insight
into the relationship between drug concentration, efficacy, and toxicity.
Venous blood sampling is currently the standard method used for TDM. However,
this method is quite invasive and can cause psychological distress in patients
with pre-existing fear of injections. To reduce the patient's burden, other
methods such as capillary microsampling have been designed, in which a finger
prick is sufficient for blood collection. This is way less invasive than
venipuncture and enables patients to perform one or more finger pricks
themselves. Furthermore, capillary microsampling offers the possibility to
collect blood at home, resulting in fewer hospital visits, improving the
patient experience, and reducing the threshold for blood sampling. In this
study, we aim to validate the capillary microsampling method for olanzapine in
comparison to the venipuncture method.

Clinical validation of capillary microsampling with finger pricks for
olanzapine. The validation method is performed in accordance with the EM
guideline. In this process, the analytical methods are assessed for
selectivity, carry-over, lower limit of quantification, calibration curve,
accuracy, precision, dilution, matrix effect, and stability

Cross-sectional observational study

Participating in this study will have negligible risk for the patients and
during the study the participating patients will have no benefits. When the
method is successfully validated, capillary capillary microsampling can be a
great benefit to a larger group of patients that use drugs that require TDM.