Induction of Cyp1a in the Beagle Dog by an Inhibitor of Kinase Insert Domain-Containing Receptor: Differential Effects in Vitro and in Vivo on Mrna and Functional Activity

Abstract

ABSTRACT:Compound I [3-[5-(4-methanesulfonyl-piperazin-1-ylmethyl)-1H-indol-2-yl]-1H-quinolin-2-one] is a potent inhibitor of human kinase insert domain-containing receptor (KDR kinase), which is under investigation for the treatment of cancer. Bile duct-cannulated male beagle dogs were administered 6 mg/kg compound I q.d. for 14 days. There was an approximately 2.5-fold decrease in the mean plasma area under the curve of I on days 7 and 14 (ϳ11.3 M ⅐ h), relative to day 1 (28.2 M ⅐ h). In the dog, compound I was eliminated by metabolism, with a major pathway being aromatic hydroxylation and subsequent sulfation to form the metabolite M3. Metabolic profiling suggested that the pathway leading to the formation of the sulfated conjugate M3 was induced upon multiple dosing of I. Studies conducted in vitro suggested that CYP1A1/2 was responsible for the formation of the hydroxylated metabolite, which is sulfated to yield M3. Additional studies confirmed induction of CYP1A protein and activity in the livers of dogs treated with I. However, studies in a dog hepatocyte model of induction showed a surprising decrease both in CYP1A mRNA and enzymatic activity in the presence of I, emphasizing the need to consider the results from a variety of in vitro and in vivo studies in deriving an understanding of the metabolic fate of a drug candidate. It is concluded that the autoinduction observed after multiple treatments with compound I occurs since compound I is both an inducer and a substrate for dog CYP1A.

Does In Vitro Cytochrome P450 Downregulation Translate to In Vivo Drug‐Drug Interactions? Preclinical and Clinical Studies With 13‐cis‐Retinoic Acid

“…The data collected show a clear disconnect in IVIVE with in vitro CYP2D6 downregulation translating to induction of CYP2D6 in the clinic. These data are similar to previous findings in dogs, 23 in which an investigational drug was shown to downregulate CYP1A mRNA in beagle hepatocytes yet in vivo studies showed CYP1A induction. In contrast, transcriptional downregulation and increased proteasomal degradation of CYPs in response to increased proinflammatory cytokines, such as interleukin (IL)-6 and IL-1β [24][25][26] corresponds to in vivo suppression of CYPs.…”

Characterization of Substrate Specificity of Dog CYP1A2 Using CYP1A2-Deficient and Wild-Type Dog Liver Microsomes

“…EROD activity is used as an in vitro CYP1A1/2 marker activity not only in humans but also in dogs (Graham et al, 2002). Although heterologously expressed dog CYP1A1 and CYP1A2 catalyzed EROD activity, the contribution of CYP1A2 in EROD activity in dog liver microsomes has been unknown (Gibson et al, 2005). Our results suggested that CYP1A2 is largely responsible for EROD activity in dog liver microsomes.…”

CYP2C75-Involved Autoinduction of Metabolism in Rhesus Monkeys of Methyl 3-Chloro-3′-fluoro-4′-{(1R)-1-[({1-[(trifluoroacetyl)amino]cyclopropyl}carbonyl)amino]ethyl}-1,1′-biphenyl-2-carboxylate (MK-0686), a Bradykinin B1 Receptor Antagonist

“…Unlike several reported autoinduction cases where the induced P450 enzymes dominated the total clearance of the compounds in either human or preclinical species (Gibson et al, 2005;Shimizu et al, 2006;Kitamura et al, 2007), MK-0686 was eliminated via both hydrolytic reactions and CYP2C75-mediated oxidation in rhesus monkeys. The contribution of the former pathways seemed to be equal to or greater than the latter for the total clearance of MK-0686 (Fig.…”

“…jpet.aspetjournals.org first two parameters is well precedented, tools for identifying important P450s are not readily available for preclinical species. Only limited efforts have been reported to investigate the P450 isozymes involved in autoinduction in dogs (Gibson et al, 2005) and rats (Kitamura et al, 2007). The remarkable reduction of systemic exposure of MK-0686 in rhesus monkeys after repeated oral administration presents the first report of autoinduction attributed to rhesus CYP2C75.…”

“…Rhesus hepatocytes were prepared in-house by a similar method described previously (Gibson et al, 2005). Cells were plated and cultured for 48 h in InVitroGRO CP plating medium (Celsis In Vitro Technologies, Baltimore, MD), with media replaced every 24 h. Cultured hepatocytes were maintained at 37°C, 95% humidity, and 5% CO 2 on collagen type I-coated plates.…”