HER2-Targeted Therapy Works Even at Very Low HER2 Levels

Abstract: New breast cancer trial results show that the HER2-targeting drug trastuzumab deruxtecan is effective even when tumors express very low levels of HER2. Compared with chemotherapy, the drug increased progression-free survival by 5 months in patients with low or very low HER2 levels. However, the drug also increased the rate of severe and fatal side effects.