TBCRC 048: Phase II Study of Olaparib for Metastatic Breast Cancer and Mutations in Homologous Recombination-Related Genes.

PARP inhibition is an effective treatment for patients with MBC and g or s/ mutations, significantly expanding the population of patients with breast cancer likely to benefit from PARPi beyond g/ mutation carriers. These results emphasize the value of molecular characterization for treatment decisions in MBC.