HPLC determination and pharmacokinetics of the new original domestic drug dibufelon

A simple, specific, sensitive, and precise high-performance liquid chromatography (HPLC) assay with UV detection has been developed for quantitative determination of fenozan acid in human blood plasma. Using this method, the pharmacokinetics of the new domestic preparation dibufelon (OOO Consortium-PIK, Russia) were investigated after a single peroral administration of an 800-mg dose in 12 healthy volunteers. It is established that the drug is rapidly absorbed from the GI tract into the systemic blood flow [C max ,178 ± 29 ng/mL; T max, 3.9 ± 0.5 h; AUC ₀₋∞, 1434 ± 269 (ng ∙ h)/mL; C max/AUC ₀₋∞, 0.135 ± 0.011 L/h], rather well retained in humans (MRT, 8.6 ± 0.8 h; T ₁/₂, 5.3 ± 0.8 h), and, despite a rapid total clearance (Cl t ,824 ± 167 L/h), penetrates well into organs and tissues (V Z , 5590 ± 1204 L).