We evaluated ex vivo antitumor activity of LP-184 in selected PDX models representing lung, pancreatic and prostate cancers with high PTGR1 and known HR defects. 17.6% of lung adenocarcinomas (n = 517), 4.5% of pancreatic adenocarcinomas (n = 179) and 9.6% of prostate adenocarcinomas (n = 498) displayed elevated PTGR1 along with damaging HR related mutations, and are likely to be responsive to LP-184 based on analysis of TCGA data.