Phase III Trial of Neoadjuvant Durvalumab (NSC 778709) plus Chemotherapy versus Chemotherapy Alone for Adults with MammaPrint Ultrahigh (MP2) Hormone Receptor (HR) Positive /Human Epidermal Growth Factor Receptor (HER2) Negative Stage II-III Breast Cancer

Objective:

Primary Objective:

• To compare breast cancer event-free survival between participants randomized to standard of care neoadjuvant chemotherapy alone versus standard of care neoadjuvant chemotherapy concurrent with durvalumab.

Secondary Objectives:

• To compare pathologic complete response rates (ypT0/is, ypN0) in participants randomized to standard of care chemotherapy alone vs. standard of care neoadjuvant chemotherapy concurrent with durvalumab
• To compare residual cancer burden distribution between participants randomized to standard of care neoadjuvant chemotherapy vs. standard of care neoadjuvant chemotherapy concurrent with durvalumab
• To compare distant relapse-free survival between participants randomized to standard of care neoadjuvant chemotherapy vs. standard of care neoadjuvant chemotherapy concurrent with durvalumab
• To compare overall survival between participants randomized to standard of care neoadjuvant chemotherapy vs. standard of care neoadjuvant chemotherapy concurrent with durvalumab
• To compare the frequency and severity of toxicities between participants randomized to standard of care neoadjuvant chemotherapy vs. standard of care neoadjuvant chemotherapy concurrent with durvalumab among those who initiate the assigned treatment.