Development of an UPLC-MS/MS micromethod for quantitation of cinitapride in plasma and its application in a pharmacokinetic interaction trial.

Aim: Cinitapride (CIN) is a benzamide-derived molecule used for the treatment of gastroesophageal reflux and dyspepsia. Its pharmacokinetics are controversial due to the use of supratherapeutic doses and the lack of sensitive methodology. Therefore, a sensitive and accurate micromethod was developed for its quantitation in human plasma.

Results: CIN was extracted from 300 µl of heparinized plasma by liquid-liquid extraction using cisapride as internal standard, and analyzed with an ultra performance liquid chromatograph employing positive multiple-reaction monitoring-MS.

Conclusion: The method proved to be rapid, accurate and stable within a range between 50 and 2000 pg/ml and was successfully validated and applied in a pharmacokinetic interaction trial, where it was demonstrated that oral co-administration of simethicone does not modify the bioavailability of CIN.