Halofuginone hydrochloride (RU-19110), a derivative of Febrifugine, functions as a competitive inhibitor of prolyl-tRNA synthetase, displaying a Ki value of 18.3 nM. This compound effectively inhibits type-I collagen synthesis, providing therapeutic benefits in osteoarthritis (OA) by impeding TGF-β signaling. Additionally, it serves as a potent pulmonary vasodilator, mainly through the activation of Kv channels and the inhibition of various calcium channels including voltage-gated, receptor-operated, and store-operated ones. Beyond its vascular effects, Halofuginone hydrochloride exhibits a broad spectrum of biological activities, including anti-malarial, anti-inflammatory, anti-cancer, and anti-fibrotic properties, supported by multiple studies.