Abstract

Poster Presentations

Day 1, May 15（Mon.）　　Room P (Foyer, Room 1004-1007)

1P-43　　PDF

Structure analysis of unknown metabolites of abiraterone in human serum

(¹Mukogawa Women's Univ., ²Osaka Medical and Pharmaceutical Univ., ³Mukogawa Women's Univ.)
^oShizuyo Horiyama¹, Noboru Hayama², Hiroki Yoneyama², Yoshihide Usami², Jun Haginaka³

Abiraterone (Abi) used for the treatment of castration-resistant prostate cancer is metabolized by 3β-hydroxysteroid dehydrogenase to Δ⁴-abiraterone (D4A), which is more active than Abi. D4A is metabolized by 5α- and 5β-reductase to keto-5α- and keto-5β-Abi, which are further metabolized to their hydroxy metabolites, 3α-OH-5α-Abi and 3β-OH-5α-Abi, and 3α-OH-5β-Abi and 3β-OH-5β-Adi. When analyzing a human serum sample after administration of Abi acetate, an unknown peak appeared at　m/z 348.2322 (t_R 12.72 min) in the extracted ion chromatogram. To determine the structure of this unknown compound, Δ¹-5α-Abi and Δ¹-5β-Abi were synthesized and analyzed by LC/MS. These results suggest that the unknown compound is Δ¹-5β-Abi