THZ-P1-2 is a novel, specific inhibitor of PI5P4K that effectively targets PI5P4Kalpha. With an IC 50 of 190 nM, THZ-P1-2 selectively inhibits PI5P4Kalpha by forming covalent bonds with cysteine residues located on a disordered loop present in PI5P4Kalpha/beta/gamma. This mechanism not only disrupts autophagy but also elevates TFEB signaling. Moreover, THZ-P1-2 exhibits potent anticancer effects in leukemia cell lines, making it a promising candidate for therapeutic applications.