In a phase 1 dose-escalation study in non-Japanese patients with germline BRCA1/2 mutations in several types of advanced cancers [9], the primary AEs related to talazoparib (dose levels 0.025 to 1.1 mg QD) were hematologic (anemia, thrombocytopenia, and neutropenia) and generally resolved with drug interruption and/or dose reduction and routine medical intervention [9]. Here, BRCA1 is linked to Decreased total neutrophil count.