BRCA1 and neutropenia: •The OlympiA trial: 3-year IDFS, 3-year DDFS, and OS were significantly higher in the olaparib group.•The TBCRC 048 trial: The ORR was 33% in germline mutations of non-BRCA1/2 HR-related genes and 31% in somatic mutations of BRCA1/2 or other HR-related genes; the median PFS for gPALB2 and sBRCA1/2 mutation carriers were 13.3 and 6.3 months; among the gPALB2 and sBRCA1/2 mutation carriers, responses occurred in 67% of TNBC patients.•The olaparib combination with carboplatin trial: Hematologic toxicity was the most common AE, with 36% of patients having Grade 3 and 4 neutropenia.