ZT-12-037-01 is a specific and ATP-competitive STK19 inhibitor with IC50s of 23.96 nM and 27.94 nM for STK19 (WT) and STK19 (D89N), respectively. It displays extremely high kinase selectivity using KINOMEscan against a panel of 468 diverse kinases using an in vitro ATP-site competition binding assay at 1 μM.