Structure-Based Design of Novel Class II c-Met Inhibitors: 1. Identification of Pyrazolone-Based Derivatives

Deregulation of c-Met receptor tyrosine kinase activity leads to tumorigenesis and metastasis in animal models. More importantly, the identification of activating mutations in c-Met, as well as <i>MET</i> gene amplification in human cancers, points to c-Met as an important target for cancer therapy. We have previously described two classes of c-Met kinase inhibitors (class I and class II) that differ in their binding modes and selectivity profiles. The class II inhibitors tend to have activities on multiple kinases. Knowledge of the binding mode of these molecules in the c-Met protein led to the design and evaluation of several new class II c-Met inhibitors that utilize various 5-membered cyclic carboxamides to conformationally restrain key pharmacophoric groups within the molecule. These investigations resulted in the identification of a potent and novel class of pyrazolone c-Met inhibitors with good in vivo activity

Discovery of Potent and Selective 8‑Fluorotriazolopyridine c‑Met Inhibitors

The overexpression of c-Met and/or hepatocyte growth factor (HGF), the amplification of the MET gene, and mutations in the c-Met kinase domain can activate signaling pathways that contribute to cancer progression by enabling tumor cell proliferation, survival, invasion, and metastasis. Herein, we report the discovery of 8-fluorotriazolopyridines as inhibitors of c-Met activity. Optimization of the 8-fluorotriazolopyridine scaffold through the combination of structure-based drug design, SAR studies, and metabolite identification provided potent (cellular IC₅₀ < 10 nM), selective inhibitors of c-Met with desirable pharmacokinetic properties that demonstrate potent inhibition of HGF-mediated c-Met phosphorylation in a mouse liver pharmacodynamic model

Discovery of (<i>R</i>)‑6-(1-(8-Fluoro-6-(1-methyl‑1<i>H</i>‑pyrazol-4-yl)-[1,2,4]triazolo[4,3‑<i>a</i>]pyridin-3-yl)ethyl)-3-(2-methoxyethoxy)-1,6-naphthyridin-5(6<i>H</i>)‑one (AMG 337), a Potent and Selective Inhibitor of MET with High Unbound Target Coverage and Robust In Vivo Antitumor Activity

Deregulation of the receptor tyrosine kinase mesenchymal epithelial transition factor (MET) has been implicated in several human cancers and is an attractive target for small molecule drug discovery. Herein, we report the discovery of compound <b>23</b> (AMG 337), which demonstrates nanomolar inhibition of MET kinase activity, desirable preclinical pharmacokinetics, significant inhibition of MET phosphorylation in mice, and robust tumor growth inhibition in a MET-dependent mouse efficacy model