Evaluation of Deuterium-Labeled JNJ38877605: Pharmacokinetic, Metabolic, and in Vivo Antitumor Profiles

c-Met inhibitor JNJ38877605 has proven curative as an antitumor agent, while its clinical study was terminated due to renal toxicity. It was reported that the renal toxicity was caused by the poor solubility of its aldehyde oxidase (AO) metabolites. Therefore, blocking AO oxidation of JNJ38877605 might diminish the toxic metabolites and overcome the renal toxicity. Compound 3, the AO metabolic site deuterated JNJ38877605, was then synthesized as the target molecule. In vitro monkey liver S9 fraction incubation of 3 manifested that the renal toxic metabolite M2-2 was significantly reduced, which connoted that this deuteration has partly blocked AO oxidation. After po. nasal gavage to cynomolgus monkeys, compound 3 revealed decreased AO metabolites M2-2 and M3-2 in the plasma as well as 1.88-fold AUC and 1.56-fold C-max compared with JNJ38877605, indicating that deuterium replacement significantly blocked AO metabolism in vivo. Besides, metabolic profiles of 3 were investigated by analysis of the plasma and the urine of the po. administrated cynomolgus monkeys. Moreover, after oral administration to the EBC-1 tumor-bearing nude mice, compound 3 exhibited a better antitumor efficacy than JNJ38877605. In conclusion, deuteration on the AO metabolic site of JNJ38877605 improved its AO metabolism, oral exposure, as well as in vivo antitumor efficacy.