Talazoparib is readily orally bioavailable, with more than 40% absolute oral bioavailability in rats when dosed in carboxylmethyl cellulose. Oral administration of Talazoparib elicits remarkable antitumor activity; xenografted tumors that carry defects in DNA repair due to BRCA mutations or PTEN deficiency are profoundly sensitive to oral Talazoparib treatment at well-tolerated doses in mice. Synergistic or additive antitumor effects are also found when Talazoparib is combined with temozolomide, SN38, or platinum drugs[1].