Multinational phase 3 trial of neoadjuvant nivolumab plus chemotherapy for early ER-positive HER2-negative breast cancer

Patients with ER-positive HER2-negative early breast cancer (HR+ HER- EBC) have low pathological complete response (pCR) rates with neoadjuvant chemotherapy. The multinational phase 3 CheckMate 7FL trial evaluated addition of nivolumab to neoadjuvant chemotherapy for these patients. Patients were randomized to nivolumab plus chemotherapy (n=257) or placebo plus chemotherapy (n=253). The primary endpoint of pCR was significantly higher in the nivolumab group compared with the placebo group (24.5% versus 13.8%; p=0.0021) with higher benefit from nivolumab among patients with PD-L1 positive tumors (≥ 1%: 44.3% versus 20.2%) and higher stromal tumor-infiltrating lymphocyte levels (> 1%: 44.3% versus 21.1%). The authors conclude that adding nivolumab to neoadjuvant chemotherapy significantly increased pCR rates in high-risk HR+ HER2- EBC, particularly among patients with higher PD-L1 expression or sTIL levels.