Quantification of CLR1401, a novel alkylphosphocholine anticancer agent, in rat plasma by hydrophilic interaction liquid chromatography–tandem mass spectrometric detection

A rapid and specific LC–MS/MS based bioanalytical method was developed and validated for the determination of 18-(p-iodophenyl)octadecyl phosphocholine (CLR1401), a novel phosphocholine drug candidate, in rat plasma. The optimal chromatographic behavior of CLR1401 was achieved on a Kromasil silica column (50 mm × 3 mm, 5 μm) under hydrophilic interaction chromatography. The total LC analysis time per injection was 2.8 min with a flow rate of 1.5 mL/min under gradient elution. Liquid–liquid extraction in a 96-well format using ethyl acetate was developed and applied for method validation and sample analysis. The method validation was conducted over the curve range of 2.00–1000 ng/mL using 0.0500 mL of plasma sample. The intra- and inter-day precision and accuracy of the quality control samples at low, medium, and high concentration levels showed ≤ 5.9% relative standard deviation (RSD) and −10.8 to −1.4% relative error (RE). The method was successfully applied to determine the toxicokinetics of CLR1401 in rats from three dose groups of 0.4, 4.0, and 10.0 mg/kg/day via intravenous administration.