title: Impact of hydrolysis-mediated clearance on the pharmacokinetics of novel anaplastic lymphoma kinase inhibitors.
abstract: Compound 1 [(E)-4-fluoro-N-(6-((4-(2-hydroxypropan-2-yl)piperidin-1-yl)methyl)-1-((1S,4S)-4-(isopropylcarbamoyl)cyclohexyl)-1H-benzo[d]imidazol-2(3H)-ylidene)benzamide], a new, potent, selective anaplastic lymphoma kinase (ALK) inhibitor with potential application for the treatment of cancer, was selected as candidate to advance into efficacy studies in mice. However, the compound underwent mouse-specific enzymatic hydrolysis in plasma to a primary amine product (M1). Subsequent i.v. pharmacokinetics studies in mice showed that compound 1 had high clearance (CL) and a short half-life. Oral dose escalation studies in mice indicated that elimination of compound 1 was saturable, with higher doses achieving sufficient exposures above in vitro IC(50). Chemistry efforts to minimize hydrolysis resulted in the discovery of several analogs that were stable in mouse plasma. Three were taken in vivo into mice and showed decreased CL corresponding to increased in vitro stability in plasma. However, the more stable compounds also showed reduced potency against ALK. Kinetic studies in NADPH-fortified and unfortified microsomes and plasma produced submicromolar K(m) values and could help explain the saturation of elimination observed in vivo. Predictions of CL based on kinetics from hydrolysis and NADPH-dependent pathways produced predicted hepatic CL values of 3.8, 3.0, 1.6, and 1.2 l/h⋅kg for compound 1, compound 2 [(E)-3,5-difluoro-N-(6-((4-(2-hydroxypropan-2-yl)piperidin-1-yl)methyl)-1-((1s,4s)-4-(isopropylcarbamoyl)cyclohexyl)-1H-benzo[d]imidazol-2(3H)-ylidene)benzamide], compound 3 [(E)-3-chloro-5-fluoro-N-(6-((4-(2-hydroxypropan-2-yl)piperidin-1-yl)methyl)-1-((1s,4s)-4-(isopropylcarbamoyl)cyclohexyl)-1H-benzo[d]imidazol-2(3H)-ylidene)benzamide], and compound 4 [(E)-N-(6-((4-(2-hydroxypropan-2-yl)piperidin-1-yl)methyl)-1-((1s,4s)-4-(isopropylcarbamoyl)cyclohexyl)-1H-benzo[d]imidazol-2(3H)-ylidene)-3-(trifluoromethyl)benzamide], respectively. The in vivo observed CLs for compounds 1, 2, 3, and 4 were 5.52, 3.51, 2.14, and 2.66 l/h⋅kg, respectively. These results indicate that in vitro metabolism kinetic data, incorporating contributions from both hydrolysis and NADPH-dependent metabolism, could be used to predict the systemic CL of compounds cleared via hydrolytic pathways provided that the in vitro assays thoroughly investigate the processes, including the contribution of other metabolic pathways and the possibility of saturation kinetics.
authors.affiliation: Department of Pharmacokinetics and Drug Metabolism, Amgen, Inc., 360 Binney St., Cambridge, MA 02142, USA. yteffera@amgen.com
authors.forename: Yohannes
authors.initials: Y
authors.lastname: Teffera
authors.forename: Loren M
authors.initials: LM
authors.lastname: Berry
authors.forename: Rachael L
authors.initials: RL
authors.lastname: Brake
authors.forename: Richard T
authors.initials: RT
authors.lastname: Lewis
authors.forename: Douglas C
authors.initials: DC
authors.lastname: Saffran
authors.forename: Earl
authors.initials: E
authors.lastname: Moore
authors.forename: Jingzhou
authors.initials: J
authors.lastname: Liu
authors.forename: Zhiyang
authors.initials: Z
authors.lastname: Zhao
mesh_terms: D000077548:Anaplastic Lymphoma Kinase; D000818:Animals; D019540:Area Under Curve; D002853:Chromatography, Liquid; D006868:Hydrolysis; D020128:Inhibitory Concentration 50; D008297:Male; D051379:Mice; D047428:Protein Kinase Inhibitors / Q000097:blood / Q000493:pharmacokinetics*; D051381:Rats; D017207:Rats, Sprague-Dawley; D020794:Receptor Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors*; D053719:Tandem Mass Spectrometry
chemical_list: D047428:Protein Kinase Inhibitors; C000626174:Alk protein, mouse; C000626175:Alk protein, rat; D000077548:Anaplastic Lymphoma Kinase; D020794:Receptor Protein-Tyrosine Kinases