HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC METHOD FOR THE DETERMINATION OF A NOVEL THYMIDYLATE SYNTHASE INHIBITOR, AG-331, IN HUMAN SERUM

AG 331 is a novel thymidylate synthase inhibitor currently in Phase I clinical trial. To determine the pharmacokinetic parameters of AG 331 in human subjects, a suitable analytical method was developed using hi gh-performance liquid chromatography. Serum and urine samples were pre pared using both solid-phase extraction and solvent extraction. Either 4,4'-diaminodiphenyl sulfone or benz[cd]indole-2(1H)-one were used as internal standards for the method. A reversed-phase C-18 analytical c olumn completely resolved the drug and internal standard peaks from no n-specific substances present in biological matrix. The method was val idated for precision, accuracy, and reproducibility in serum and was l inear over a concentration range of 50-2000 ng/ml, with a limit of det ection of 20.0 ng/ml and a quantifiable limit of 50 ng/ml.