Multicenter randomized phase 2 trial of carboplatin with or without atezolizumab for metastatic triple-negative breast cancer

The value of combining platinum compounds with PD-1/PD-L1 targeted immunotherapy for metastatic triple-negative breast cancer (mTNBC) has not been extensively determined. The randomized phase 2 TBCRC 043 trial, at 6 centers in the USA, evaluated addition of atezolizumab to carboplatin for mTNBC. The trial, including 106 patients, found that progression-free and overall survival were significantly improved with carboplatin plus atezolizumab versus carboplatin alone. Tumor-infiltrating lymphocytes, mutation burden, obesity, and increased blood glucose levels were associated with greater benefit on the combination.