Study of Patritumab Deruxtecan Plus Pembrolizumab With Other Anticancer Agents in Participants With High-Risk Early-Stage Triple-Negative or Hormone Receptor-Low Positive/HER-2 Negative Breast Cancer (MK-1022-010, HERTHENA-Breast-03)

Study Summary

Researchers are looking for new ways to treat triple-negative breast cancer (TNBC) and hormone receptor (HR) low positive/human epidermal growth factor receptor-2 (HER2) negative breast cancer. The main goals of this study are to learn: * About the safety of the study treatments and if people tolerate them * If people who receive patritumab deruxtecan, pembrolizumab, and chemotherapy before surgery have fewer cancer cells removed during surgery compared to those who receive only pembrolizumab (pembro) and chemotherapy.