MPL-5821

**MPL-5821** is a myeloid-specific, macrophage-targeted inhibitor of p38 mitogen-activated protein kinase (MAPK), developed using Macrophage Pharma's proprietary ESM™ (Enzyme Substrate Mimetic Targeting) technology to selectively modulate macrophage plasticity in the tumor microenvironment. It inhibits IL-10 production while enhancing LPS-stimulated IL-12p70 secretion, promotes M1 macrophage polarization, reverses M2 macrophage-induced T-cell suppression, and spares non-myeloid immune cells like lymphocytes to preserve key anti-tumor immune axes such as IL-12p70/IFNγ. Initially developed by Chroma Therapeutics Ltd. (later acquired and rebranded elements contributing to Macrophage Pharma), it shows preclinical promise in immuno-oncology, particularly for enhancing tumor immune responses in models like patient-derived lung cancer tumor microspheroids, with plans for clinical studies announced around 2018.[1][2][3][5][9]

Other names

ESM p38 MAPK inhibitor