Discovery of Clinical Candidate 1-(4-(3-(4-(1H-Benzo[d]imidazole-2-carbonyl)phenoxy)pyrazin-2-yl)piperidin-1-yl)ethanone (AMG 579), A Potent, Selective, and Efficacious Inhibitor of Phosphodiesterase 10A (PDE10A).
Hu, E., Chen, N., Bourbeau, M.P., Harrington, P.E., Biswas, K., Kunz, R.K., Andrews, K.L., Chmait, S., Zhao, X., Davis, C., Ma, J., Shi, J., Lester-Zeiner, D., Danao, J., Able, J., Cueva, M., Talreja, S., Kornecook, T., Chen, H., Porter, A., Hungate, R., Treanor, J., Allen, J.R.(2014) J Med Chem 57: 6632-6641
- PubMed: 25062128
- DOI: https://doi.org/10.1021/jm500713j
- Primary Citation of Related Structures:
4PHW - PubMed Abstract:
We report the identification of a PDE10A clinical candidate by optimizing potency and in vivo efficacy of promising keto-benzimidazole leads 1 and 2. Significant increase in biochemical potency was observed when the saturated rings on morpholine 1 and N-acetyl piperazine 2 were changed by a single atom to tetrahydropyran 3 and N-acetyl piperidine 5. A second single atom modification from pyrazines 3 and 5 to pyridines 4 and 6 improved the inhibitory activity of 4 but not 6. In the in vivo LC-MS/MS target occupancy (TO) study at 10 mg/kg, 3, 5, and 6 achieved 86-91% occupancy of PDE10A in the brain. Furthermore, both CNS TO and efficacy in PCP-LMA behavioral model were observed in a dose dependent manner. With superior in vivo TO, in vivo efficacy and in vivo PK profiles in multiple preclinical species, compound 5 (AMG 579) was advanced as our PDE10A clinical candidate.
Organizational Affiliation:
Department of Medicinal Chemistry, ‡Department of Molecular Structure and Characterization, §Department of Pharmacokinetics and Drug Metabolism, ∥Department of Neuroscience, Amgen Inc. , One Amgen Center Drive, Thousand Oaks, California 93012-1799, United States.