Molecular glue

A molecular glue is a type of small molecule that modulates protein–protein interactions in cells by enhancing the affinity between proteins. These compounds can induce novel interactions between proteins (type I) or stabilize pre-existing ones (type II), offering an alternative strategy to traditional drug discovery. Molecular glues have shown promise in targeting proteins previously considered "undruggable" by conventional methods. They work through various mechanisms, such as promoting protein degradation or inhibiting protein function, and are being studied for potential use in treating cancer, neurodegenerative disorders, and other diseases.

Unlike PROTACs, which are rationally designed heterobifunctional molecules that contain two covalently linked ligands that bind respectively to a target protein and an E3 ligase, molecular glues are small, monofunctional compounds typically discovered serendipitously through screening or chance observations.