Structure-Based Virtual Screening Identifies TREM2-Targeted Small Molecules that Enhance Microglial Phagocytosis

Abstract Triggering receptor expressed on myeloid cells 2 (TREM2) is a microglia-specific receptor whose activation promotes phagocytosis and neuroprotection in Alzheimer’s disease (AD) and related neurodegenerative disorders. While therapeutic efforts have largely focused on antibodies, small molecule TREM2 modulators remain limited. Here, we applied a structure- based virtual screening workflow targeting a putative allosteric site on TREM2, guided by PyRod-derived pharmacophores from molecular dynamics simulations. Screening of the Enamine Collection yielded 20 candidate compounds, three of which demonstrated binding in TRIC assays. The top hit, EN020 , exhibited a KD of 14.2 µM (MST) and 35.9 µM (SPR), and significantly enhanced microglial phagocytosis in BV2 cells outperforming the known TREM2 agonist VG-3927 . A preliminary structure–activity relationship (SAR) study, including synthetic and catalog-derived analogs, highlighted a narrow tolerance for scaffold modifications, with only T2V002 retaining partial TREM2 binding affinity. This work identifies EN020 as a novel small molecule TREM2 modulator with functional activity, providing a framework for rational optimization toward potential AD therapeutics.