DF1001-001 is a study of a new molecule that targets natural killer (NK) cells and T-cell
activation signals to specific receptors on cancer cells. The study will occur in two phases.
The first phase will be a dose escalation phase, enrolling patients with various types of
solid tumors that express human epidermal growth factor receptor 2 (HER2). The second phase
will include a dose expansion using the best dose selected from the first phase of the study.
Multiple cohorts will be opened with eligible patients having either HER2 activated non-small
cell lung cancer, hormone receptor (HR) positive HER2 negative metastatic breast cancer, or
HER2 positive metastatic breast cancer. DF1001-001 will be administered as monotherapy or in
combination; combinations are DF1001 + nivolumab, DF1001 + Nab paclitaxel, and DF1001 +
sacituzumab govitecan-hziy.

This phase III trial compares the effect of radiation therapy combined with hormonal therapy versus hormonal therapy alone in treating patients with low risk, early stage breast cancer with Oncotype Dx Recurrence =< 18. Oncotype DX is a laboratory test which results in a score that is used to help predict whether breast cancer will spread to other parts of the body or come back. Radiation therapy uses high doses of radiation to kill cancer cells and shrink tumors but may result in some side effects. Hormones called estrogen and progesterone may contribute to the growth of breast tumor cells. Hormone therapy, also called endocrine therapy, may stop the growth of tumor cells by blocking or removing these hormones. This clinical trial may help researchers understand if patients with low-risk, early stage breast cancer who have Oncotype recurrence score of =< 18 can safely omit radiation therapy and only be treated with hormonal therapy without losing any radiation treatment benefit.