EXR-303

EXR-303 is a discontinued small molecule drug candidate that was developed by ExSAR Corp for the treatment of Motor Neuron Disease (MND), specifically Amyotrophic Lateral Sclerosis (ALS). The compound was developed using ExSAR's proprietary pharmacological chaperone platform, which focused on identifying small molecules capable of stabilizing proteins to prevent toxic misfolding and aggregation—a hallmark of neurodegenerative pathology. While specific molecular target details for EXR-303 were not publicly disclosed, ExSAR's research in MND was heavily centered on the stabilization of proteins such as Superoxide Dismutase 1 (SOD1). Development of the program was discontinued as ExSAR Corp became inactive and its pipeline was suspended.