DISTRIBUTION OF FENOFIBRIC ACID IN LIPOPROTEIN FRACTIONS OF PATIENTS

The antidyslipidemic agent fenofibrate (procetofen) is hydrolysed in v ivo to its main active metabolite - fenofibric (procetofenic) acid. Th is metabolite is usually determined in pharmacokinetic studies, becaus e plasma concentrations of fenofibrate are practically undetectable. P resented study is focussed on the distrubution of fenofibric acid into lipoprotein (VLDL, LDL, IDL and HDL) fractions of human and (for comp arison) minipig blood plasma, which has not been studied yet. in order to obtain more accurate results, a new HPLC method based on the use o f newly synthetized internal standards was developed. Four homologues of fenofibric acid prepared have identical chromophoric part of their molecules and hence the same UV spectra as fenofibric acid. From this point of view, these standards are more suitable for determination of fenofibric acid than the formerly used ones - naproxen or bezafibrate. Fenofibric acid levels in the high density lipoprotein fraction has b een shown to be significantly higher (in both human and minipig plasma ) than in the other lipoprotein fractions.