PT - JOURNAL ARTICLE AU - G Cassinelli AU - E Configliacchi AU - S Penco AU - G Rivola AU - F Arcamone AU - A Pacciarini AU - L Ferrari TI - Separation, characterization, and analysis of epirubicin (4'-epidoxorubicin) and its metabolites from human urine. DP - 1984 Jul 01 TA - Drug Metabolism and Disposition PG - 506--510 VI - 12 IP - 4 4099 - http://dmd.aspetjournals.org/content/12/4/506.short 4100 - http://dmd.aspetjournals.org/content/12/4/506.full SO - Drug Metab Dispos1984 Jul 01; 12 AB - Three metabolites of the new antitumor anthracycline epirubicin (4'-epidoxorubicin, 4'-epiDX) detected by HPLC in urine of four patients treated with 75 mg/m2 of the drug, were isolated and identified. In an initial step, fluorescent metabolites present in urine, pooled during the first 24 hr after drug administration, were adsorbed on a column of a styrene divinylbenzene adsorbent. The subsequent gradient elution with aqueous methanol, followed by extraction with 1-butanol at different pH values, allowed separation of 4'-epiDX and its 13-dihydro derivative from the more polar metabolites. Each anthracycline was subsequently separated by reverse phase liquid chromatography, characterized by acid and enzymatic hydrolyses, and studied with chemical-physical analysis. In addition to the parent drug, its 13-dihydro derivative and 4'-O-beta-D-glucuronyl-4'-epiDX which were structurally characterized, a glucuronide conjugate of 13-dihydro-4'-epiDX was identified. In four patients analyzed, approximately 12% of the total administered dose was estimated, by reverse phase HPLC and fluorescence detection, to be excreted in the 0-24-hr pooled urine. 4'-EpiDX accounted for 57% of the total excreted fluorescent anthracyclines, its 4'-O-beta-D-glucuronide for 32%, 13-dihydro-4'-epiDX for 7%, and its glucuronide for 3%, average values.