SRX3177 is a potent triple inhibitor targeting CDK4/6, PI3K, and BRD4, with IC50 values of 33 nM for BRD4 BD1, 89 nM for BRD4 BD2, 79 nM for PI3Kα, 83 nM for PI3Kδ, 3.18 μM for PI3Kγ, <2.5 nM for CDK4, and 3.3 nM for CDK6. By simultaneously inhibiting these key pathways, SRX3177 disrupts cancer cell signalling and exhibits significant cytotoxic effects in tumors.