AMG PERK 44 is an orally active and highly selective PERK inhibitor with an IC50 of 6 nM. AMG PERK 44 has 1000-fold and 160-fold selectivity over GCN2 (IC50=7300 nM) and B-Raf (IC50 >1000 nM), respectively[1][2].
[1]. Smith AL, et al. Discovery of 1H-pyrazol-3(2H)-ones as potent and selective inhibitors of protein kinase R-like endoplasmic reticulum kinase (PERK). J Med Chem. 2015 Feb 12;58(3):1426-41. [2]. Roest G, et al. The ER Stress Inducer l-Azetidine-2-Carboxylic Acid Elevates the Levels of Phospho-eIF2α and of LC3-II in a Ca2+-Dependent Manner. Cells. 2018 Nov 30;7(12). pii: E239.