SIMULTANEOUS QUANTIFICATION OF AN ANTIINFLAMMATORY COMPOUND (DUP-697)AND A POTENTIAL METABOLITE (X6882) IN HUMAN PLASMA AND URINE BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY

A high-performance liquid chromatographic (HPLC) method using fluoresc ence detection has been developed for the simultaneous analysis of low nanogram concentrations of an anti-inflammatory drug, mo-2-(4-fluorop henyl)-3-[4-(methylsulfonyl)phenyl] thiophene (DuP 697), and a potenti al metabolite (X6882) in human plasma and of DuP 697 in human urine. T his assay method used an EM Separations Lichrospher C-18 endcapped col umn. The mobile phase was acetonitrile-water (75:25, v/v). The detecti on of DuP 697 and X6882 was by fluorescence at excitation and emission wavelengths of 256 and 419 nm, respectively. The chromatographic syst em could separate DuP 697 from X6882, the external standard (anthracen e), and other endogenous substances present in human plasma. In human plasma the limits of quantification for DuP 697 and X6882 were 3 and 2 0 ng/ml, respectively; the limit of quantification for DuP 697 in huma n urine was 5 ng/ml. These compounds were shown to be stable in frozen (-20 degrees C) human plasma and urine for at least 9 weeks. The assa y described has been used to characterize DuP 697 pharmacokinetics aft er oral administration in humans.