LAUSR

&NA; Hydroxyurea (HU) has been used in the treatment of chronic myeloid leukaemia (CML) and other myeloproliferative malignancies. Considering patient's wide variation in clinical response to HU, a new and simple liquid chromatography‐tandem mass spectrometry (LC–MS/MS) method was developed and validated to monitor patients' compliance to treatment and investigate the pharmacokinetics of HU in patients with CML. Stable isotope labeled HU‐13C1,15N2 was used as internal standard. Plasma samples were treated with acetonitrile to precipitate protein. The supernatant was injected directly without derivatization and separated on a hydrophilic interaction liquid chromatography column. HU was quantitatively analyzed with a mobile phase of acetonitrile‐1.5 mM ammonium formate (90:10, V:V) within 3 min. The proposed method provided a linearity range of 1–200 &mgr;g/mL. The coefficients of variation for intra‐ and inter‐day precision were less than 2.07% and 4.28%, respectively, while the accuracy (bias) was in the range of −3.77 to 2.96%. This method was satisfactorily applied to the determination of HU in two patients with CML. It is suitable for supporting pharmacokinetic studies and clinical therapeutic monitoring. Graphical abstract Figure. No caption available. HighlightsA novel LC–MS/MS method for quantitative analysis of hydroxyurea (HU) in human plasma has been developed and validated.Sample preparation involved only a simple deproteinization procedure with aceronitrile and HU was separated using HILIC column within 3 min.This method has been successfully applied to the pharmacokinetics study in patients with chronic myeloid leukaemia.