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,, 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.

Discovery of IACS-9779 and IACS-70465 as Potent Inhibitors Targeting Indoleamine 2,3-Dioxygenase 1 (IDO1) Apoenzyme

“…44,45 The introduction of an ethyl substituent on the methylene linker was anticipated to minimize the metabolic cleavage of the amide bond by providing additional steric hindrance. 46,47 The single-digit nM hIDO1 cellular potency and low microsomal intrinsic clearance of compound 22 were supportive of our structural modifications. This molecule was cell permeable and had a 12.8 h half-life in mouse plasma.…”

“…We hypothesized that 21 and 22 (Figure , Table ) with a conformational constraint in the form of a [3.1.0] bicycle might offer a benefit, and potentially also improve the off-target pharmacology profile of these relatively lipophilic molecules by restricting the number of accessible conformations. − We also proposed in the concept compounds 21 and 22 , two additional changes with respect to compound 5 ; reversing the amide and introducing a substituent at the methylene linker. The benzoyl amide was a logical modification to avoid potential metabolic release of 4-chloroaniline and the assessment of the potential for genotoxicity in that event. , The introduction of an ethyl substituent on the methylene linker was anticipated to minimize the metabolic cleavage of the amide bond by providing additional steric hindrance. , The single-digit nM hIDO1 cellular potency and low microsomal intrinsic clearance of compound 22 were supportive of our structural modifications. This molecule was cell permeable and had a 12.8 h half-life in mouse plasma .…”

Discovery, synthesis and characterization of a series of (1-alkyl-3-methyl-1H-pyrazol-5-yl)-2-(5-aryl-2H-tetrazol-2-yl)acetamides as novel GIRK1/2 potassium channel activators

“…Curiously, all of the compounds tested had poor recovery in mouse plasma, leading us to theorize that the compounds were unstable due to the amidases present in plasma. 26 Several compounds were made to test this hypothesis (thioamide, 15b, amide N-methylation, and α-carbon methylation). However, all of these compounds also showed poor recovery in mouse plasma (data not shown).…”

Species differences in metabolism of a new antiepileptic drug candidate, DSP‐0565 [2‐(2′‐fluoro[1,1′‐biphenyl]‐2‐yl)acetamide]

“…These extra‐hepatic expressions of hydrolytic enzymes and their species‐differences make the evaluation of metabolism mediated via hydrolysis complicated. On the basis of the structural requirements of substrates that can be enzymatically hydrolysed, dramatic species differences in amide hydrolysis have been reported, namely those of N‐aryl isoxazolecarboxamide anticonvulsants, flumatinib, Bruton's tyrosine kinase (BTK) inhibitor, and anaplastic lymphoma kinase (ALK) inhibitors (Gong, Chen, Deng, & Zhong, ; Liu et al, ; Martin et al, ; Teffera et al, ). However, so far the investigation of clearance prediction regarding amide hydrolysis in humans has been superficial.…”

“…However, they could not carry out a comparison between the predicted and the observed human clearance, because the BTK inhibitor was not detected in human plasma after oral administration. Teffera et al () investigated the IVIVE of the ALK inhibitor, but did not include the observed human clearance in vivo in their report.…”