The EC has approved Talzenna as monotherapy treatment for adult patients with germline breast cancer susceptibility gene (gBRCA)1/2-mutations, who have human epidermal growth factor receptor 2-negative (HER2-) locally advanced (LA) or MBC.
Talazoparib, which is an inhibitor of PARP enzymes, plays a significant role in DNA repair. Preclinical studies are said to suggest that talazoparib may work by blocking PARP enzyme activity and trapping PARP at the site of DNA damage, helping to reduce cancer cell growth and cancer cell death.
Its anti-tumour activity was also noticed in human patient-derived xenograft breast cancer tumour models, which expressed mutated or wild-type BRCA1/2.
In 2018, the Talzenna also secured the approval for same indication from the US Food and Drug Administration (FDA).
The approval of Talzenna was based on data from the Embraca phase 3 study of a PARP inhibitor in gBRCA-mutated, HER2- LA or MBC.
Pfizer’s trial assessed once-daily Talzenna compared to physician’s choice standard chemotherapy (capecitabine, eribulin, gemcitabine or vinorelbine) in patients with an inherited BRCA1/2 mutation in triple-negative or HR+/HER2- LA or MBC who may have received up to three prior cytotoxic chemotherapy regimens for their advanced disease.
The trial evaluated 431 patients, of which 190 were from European countries, such as Belgium, France, Germany, Ireland, Italy, Poland, Spain and the UK.
The progression-free survival (PFS), as assessed by blinded independent central review (BICR), is the primary endpoint of the trial.
According to the company, the Talzenna significantly outperformed chemotherapy, and extended median PFS to 8.6 months compared to 5.6 months for those treated with standard chemotherapy.
Pfizer oncology international developed markets regional president Dr Andreas Penk said: “Today’s approval of TALZENNA for certain patients with advanced-stage breast cancer and an inherited BRCA mutation is the latest example of our successful precision medicine approach to drug development.
“This important milestone builds on Pfizer’s decades-long legacy of developing therapies that improve outcomes for patients with breast cancer.”