570P Hypomethylating agents synergistically combine with PARP inhibitors in ovarian cancer

Abstract

Poly (ADP-Ribose) polymerase inhibitors (PARPi’s) are currently used for first and second line maintenance therapy of ovarian cancer (OC) in patients whose tumors harbor defects in homologous recombination. Unfortunately, the rapid emergence of resistance leads to a short duration of response, and thus preventing PARPi resistance and extending the spectrum of patients who would benefit from PARP inhibition are urgent needs. While multiple drug classes have demonstrated synergy when combined with PARPi’s preclinically, head-to-head comparisons which would facilitate clinical prioritization of the most promising combinations are missing.