Study shows PARP inhibitor’s benefit for advanced breast cancer
Clayton Boldt, Ph.D.
In a randomized, Phase III trial led by MD Anderson researchers, the PARP inhibitor talazoparib extended progression-free survival (PFS) and improved quality-of-life measures over available chemotherapies for patients with metastatic HER2-negative breast cancer and mutations in the BRCA1/2 genes.
“The trial found that talazoparib provides a significant clinical benefit to all patient subgroups, including those with hormone receptor-positive and triple-negative disease,” said Jennifer Litton, M.D., associate professor of Breast Medical Oncology. “The results of this trial are quite exciting and indicate talazoparib is a novel treatment option for patients with metastatic breast cancer and BRCA mutations.”
Current therapies for metastatic cancer include sequential hormonal therapies and chemotherapies, but there are no approved therapies specifically for patients with metastatic breast cancer and a known BRCA mutation, explained Litton.
Mutations in the BRCA1/2 genes, which account for 5 to 10% of all breast cancers, cause defects in normal DNA damage repair. PARP inhibitors block an additional DNA repair pathway, and the anti-tumor effects of PARP inhibitors can be intensified in patients with BRCA mutations. Talazoparib works by not only inhibiting the PARP enzyme, but by trapping the enzyme on DNA to further prevent DNA repair.
To date, no PARP inhibitors have been approved by the Food and Drug Administration to treat breast cancers, although three previously have been approved for the treatment of certain patients with ovarian cancers.
Read more about the international trial and the potential benefits of PARP inhibitors in the MD Anderson Newsroom.