IPA-3 is a selective allosteric inhibitor of p21-activated kinases (PAKs), particularly PAK1, PAK2, and PAK3. It is widely used in research to probe the biological roles of group I PAKs in cellular signaling pathways. Its primary application lies in studying processes such as cytoskeletal remodeling, cell motility, and proliferation, which are critical in cancer and neurological research. In oncology, IPA-3 helps investigate tumor cell invasion and metastasis by blocking PAK-mediated signaling, offering insights into potential therapeutic strategies. It has also been used to explore insulin secretion mechanisms and beta-cell function, as PAK activity influences glucose-stimulated insulin release. Due to its cell-permeable nature, IPA-3 is valuable in cell-based assays, allowing direct modulation of PAK activity without genetic manipulation. However, it is mainly restricted to in vitro studies because of stability and selectivity limitations in vivo. Researchers use it as a tool compound to validate PAK-dependent pathways and assess the functional outcomes of acute PAK inhibition.