Comparison of toxicokinetic parameters of a drug and two metabolites following traditional and capillary microsampling in rat.

Following the request of a regulatory authority, a rat study was conducted to compare pharmacokinetic parameters from traditional large volume sampling and capillary microsampling. Rats were dosed with a proprietary compound in three dose groups and blood samples were collected via capillary microsampling (32 μl), immediately followed by traditional large volume sampling (300 μl) up to 24 h postdose. Resulting plasma samples were analyzed for parent drug and two metabolites. AUCs were compared between sampling techniques. There was no statistical difference between AUCs from traditional and microsampling across different doses and analytes.  Toxicokinetic parameters generated from plasma collected as a capillary microsample or traditional large volume sample are highly comparable.