Compound 4E

Compound 4E is an inhaled, small molecule inhibitor of p38α and p38β mitogen-activated protein kinases (MAPK), developed by Chiesi Farmaceutici for the treatment of chronic inflammatory lung diseases such as Chronic Obstructive Pulmonary Disease (COPD) and asthma. The compound is specifically designed for topical delivery to the respiratory tract via inhalation, which allows for high local anti-inflammatory activity while maintaining low systemic exposure to minimize off-target side effects. By blocking the p38 MAPK signaling pathway, Compound 4E suppresses the production of various proinflammatory cytokines and mediators (e.g., TNF-α, IL-8) that drive chronic airway inflammation. It was featured as a Molecule of the Month in May 2022 by Drug Hunter following its disclosure in the Journal of Medicinal Chemistry.