High-performance liquid chromatographic method for pharmacokinetic studies on the new anthracycline 4-demethoxydaunorubicin and its 13-dihydro derivative.

The anthracyclines are a group of antitumoral antibiotics with significant clinical efficacy. Among the new anthracycline derivatives, 4-demethoxydaunorubicin showed interesting biological properties in terms of both spectrum of activity and therapeutic index and was recently introduced in clinical trials. The present paper describes the analytical method developed to investigate the pharmacokinetics of this derivative. The method consists of the extraction of 4-demethoxydaunorubicin and its 13-dihydro metabolite from plasma with chloroform--1-heptanol (9:1) and re-extraction with 0.3 M phosphoric acid, separation by high-performance liquid chromatography and quantification by sensitive fluorescence detection. Plasma level curves obtained from cancer patients treated with the drug are shown.