FRAX486 is a selective inhibitor of p21-activated kinase (PAK), particularly PAK1 and PAK3 isoforms. It is primarily used in research settings to study signaling pathways involved in cell motility, cytoskeletal dynamics, and neuronal function. Due to its ability to cross the blood-brain barrier, FRAX486 is valuable in neuroscience research, especially in models of neurodevelopmental and neurodegenerative disorders such as fragile X syndrome and Alzheimer’s disease. Studies have shown that FRAX486 can reverse synaptic and behavioral deficits in animal models, making it a candidate for exploring therapeutic strategies in cognitive and psychiatric conditions. It is also used in cancer research, where PAK inhibition can suppress tumor cell proliferation, invasion, and survival, particularly in tumors with hyperactive PAK signaling. Its application remains experimental, focused on target validation and preclinical assessment of PAK-dependent pathologies.