Metabolism of epidoxorubicin in animals: absence of glucuronidation.

Metabolism of epidoxorubicin was studied in plasma of seven different animal species at 2 h after administration of 4 mg/kg. None of the animals showed significant glucuronidation of epidoxorubicin, although small amounts of the glucuronides could be detected in the rabbit. However, large differences in formation of epidoxorubicinol and 7-deoxy (7d) doxorubicinol aglycone were observed between the species. These phenomena may be relevant for interspecies differences with regard to anthracycline-induced histomorphological changes in for example, heart tissues and cardiotoxicity in relation to formation of 7d aglycones.