PARP1 and cancer: However, platinum resistance might not be sufficiently powerful to rule out clinical benefit from PARP inhibitors in BRCA‐mutated cancers, since 60% of platinum‐sensitive, BRCA1/2‐mutated ovarian cancers and 33% of platinum‐resistant, BRCA1/2‐mutated ovarian cancers in the same trial responded to olaparib.15