A new study published in Nature Medicine suggests that adding nivolumab to neoadjuvant chemotherapy can significantly increase pathological complete response (pCR) rates in patients with high-risk, early-stage estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative primary breast cancer (BC).
Researchers from the Peter MacCallum Cancer Centre in Melbourne, Australia, conducted a randomized, multicenter, phase 3 trial involving 510 patients. Patients were randomly assigned to receive anthracycline and taxane-based chemotherapy with either intravenous nivolumab or a placebo.
The study found that the nivolumab group had a significantly higher pCR rate (24.5 percent) compared to the placebo group (13.8 percent). This benefit was particularly pronounced in patients with programmed death ligand 1-positive tumors (44.3 percent versus 20.2 percent).
While five deaths occurred in the nivolumab arm, two of which were related to study drug toxicity, no deaths were reported in the placebo arm. The study did not identify any new safety signals.
The researchers hope that these findings will inform treatment decisions and ultimately improve outcomes for patients with breast cancer.