Since 2014, there are four PARPi approved for clinical use (olaparib, rucaparib, niraparib, talazoparib), indicated for the treatment of ovarian, fallopian tube and primary peritoneal carcinoma, HER2-negative breast cancer, metastatic pancreatic cancer and prostate cancer–especially (but not exclusively) when these cancers harbor breast cancer type 1 susceptibility protein 1 or 2 (BRCA1/2) mutations. The gene discussed is BRCA1; the disease is peritoneal carcinoma.