In vivo, combined BET/CDK inhibition increased T cell infiltration into PDAC tumors, and when combined with PD-L1 blockade diminished tumor growth….While CDKN2A loss promotes an immunosuppressive PDAC TME, it also renders tumors susceptible to BET/CDK inhibition....This suggests combined CDK/BET inhibition may be a personalized therapeutic approach for patients with CKDN2A-deficient PDAC, and a means to sensitize PDAC to immunotherapy.