Pfizer Inc.'s investigational drug talazoparib showed anti-tumor activity in patients with germline or inherited BRCA1/2-positive advanced breast cancer in a phase 2 trial.
The study investigated the clinical efficacy and safety of talazoparib in 83 heavily pretreated gBRCA+ advanced breast cancer patients, with objective response rate, or ORR, by independent radiology review as the primary endpoint.
A 21% ORR was observed in a group of 49 patients who previously responded to platinum-based chemotherapy and developed disease progression, while a 37% ORR was logged in a group of 35 patients who developed disease progression following at least three lines of non-platinum-based therapy, Pfizer said in a news release.
Talazoparib is also being investigated in a fully enrolled phase 3 trial in advanced gBRCA+ breast cancer.
BRCA1 and BRCA2 are human genes producing proteins for DNA repair. An alteration or mutation of either of the genes could result in a stunted progression of DNA repair, resulting in certain types of cancer.