In the studies presented here, the levels of the indirect CBL0137 target, FACT (SSRP1 and SPT16 subunits), were examined in patient PDA surgical samples and the effect of CBL0137 monotherapy or combination with gemcitabine was evaluated using patient derived PDA xenografts and PANC-1 orthotopic tumors. Here, SSRP1 is linked to Patent ductus arteriosus.