Reductions in log P Improved Protein Binding and Clearance Predictions Enabling the Prospective Design of Cannabinoid Receptor (CB1) Antagonists with Desired Pharmacokinetic Properties
作者:Bruce A. Ellsworth、Philip M. Sher、Ximao Wu、Gang Wu、Richard B. Sulsky、Zhengxiang Gu、Natesan Murugesan、Yeheng Zhu、Guixue Yu、Doree F. Sitkoff、Kenneth E. Carlson、Liya Kang、Yifan Yang、Ning Lee、Rose A. Baska、William J. Keim、Mary Jane Cullen、Anthony V. Azzara、Eva Zuvich、Michael A. Thomas、Kenneth W. Rohrbach、James J. Devenny、Helen E. Godonis、Susan J. Harvey、Brian J. Murphy、Gerry G. Everlof、Paul I. Stetsko、Olafur Gudmundsson、Susan Johnghar、Asoka Ranasinghe、Kamelia Behnia、Mary Ann Pelleymounter、William R. Ewing
DOI:10.1021/jm4010835
日期:2013.12.12
Several strategies have been employed to reduce the long in vivo half-life of our lead CB1 antagonist, triazolopyridazinone 3, to differentiate the pharmacokinetic profile versus the lead clinical compounds. An in vitro and in vivo clearance data set revealed a lack of correlation; however, when compounds with <5% free fraction were excluded, a more predictable correlation was observed. Compounds with log P between 3 and 4 were likely to have significant free fraction, so we designed compounds in this range to give more predictable clearance values. This strategy produced compounds with desirable in vivo half-lives, ultimately leading to the discovery of compound 46. The progression of compound 46 was halted due to the contemporaneous marketing and clinical withdrawal of other centrally acting CB1 antagonists; however, the design strategy successfully delivered a potent CB1 antagonist with the desired pharmacokinetic properties and a clean off-target profile.