In vitro studies on the metabolism of trabectedin (YONDELIS) in monkey and man, including human CYP reaction phenotyping.
Trabectedin (YONDELIS) is a potent anticancer agent which was recently approved in Europe for the treatment of soft tissue sarcoma. The drug is currently also in clinical development for the treatment of ovarian carcinoma. In vitro experiments were conducted to investigate the hepatic metabolism of [(14)C]trabectedin in Cynomolgus monkey and human liver subcellular fractions. The biotransformation of trabectedin was qualitatively similar in 12,000 x g supernatants of both species, and all human metabolites were also produced by the monkey. The trabectedin metabolites were identified by QTOF mass spectrometry, and HPLC co-chromatography with reference compounds. Trabectedin was metabolized via different biotransformation pathways. Most of the metabolic conversions occurred at the trabectedin A domain including mono-oxidation and di-oxidation, carboxylic acid formation with and without additional oxidation, and demethylation either without (N-demethylation to ET-729) or with additional mono-, di- or tri-oxidation. Another metabolite resulted from O-demethylation at the trabectedin C subunit, and in addition, aliphatic ring opening of the methylene dioxybridge at the B domain was detected. Overall, demethylation and oxidation played a major role in phase I metabolism of the drug. Human cDNA expressed CYPs 1A2, 2A6, 2B6, 2C8, 2C9, 2C18, 2D6, 2E1, 3A4 and 3A5 in E. coli membranes, but not CYP1B1, 2C19, and 4A11 were able to metabolize [(14)C]trabectedin. Experiments with chemical inhibitors and CYP inhibitory antibodies indicated that, at therapeutic levels, CYP3A4 is the main human CYP isoform involved in trabectedin's hepatic metabolism. In monkey and human liver microsomes, trabectedin was not substantially metabolized by glucuronidation.
Vermeir
Marc
M
Johnson & Johnson Pharmaceutical Research and Development (J&JPRD), A Division of Janssen Pharmaceutica N.V., Turnhoutseweg 30, B-2340 Beerse, Belgium. mvermeir@its.jnj.com
Hemeryck
Alex
A
Cuyckens
Filip
F
Francesch
Andres
A
Bockx
Marc
M
Van Houdt
Jos
J
Steemans
Kathleen
K
Mannens
Geert
G
Avilés
Pablo
P
De Coster
Roland
R
D000818:Animals; D018906:Antineoplastic Agents, Alkylating / Q000378:metabolism* / Q000493:pharmacokinetics; D002851:Chromatography, High Pressure Liquid; D065607:Cytochrome P-450 Enzyme Inhibitors; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis / Q000378:metabolism*; D004149:Dioxoles / Q000378:metabolism* / Q000493:pharmacokinetics; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004926:Escherichia coli / Q000378:metabolism; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D008252:Macaca fascicularis; D008297:Male; D008862:Microsomes, Liver / Q000201:enzymology / Q000378:metabolism*; D010641:Phenotype; D013045:Species Specificity; D013347:Subcellular Fractions / Q000201:enzymology / Q000378:metabolism; D044005:Tetrahydroisoquinolines / Q000378:metabolism* / Q000493:pharmacokinetics; D000077606:Trabectedin
D018906:Antineoplastic Agents, Alkylating; D065607:Cytochrome P-450 Enzyme Inhibitors; D004149:Dioxoles; D004791:Enzyme Inhibitors; D044005:Tetrahydroisoquinolines; D003577:Cytochrome P-450 Enzyme System; D000077606:Trabectedin