Unresectable Hormone Receptor Positive Breast Carcinoma

This phase I trial tests the safety, side effects, and best dose of pidnarulex in combination with trastuzumab deruxtecan in treating patients with breast cancer and other solid tumors that express varying levels of a protein called HER2 and that has spread from where it first started (primary site) to other places in the body (metastatic), that cannot be removed by surgery (unresectable), or that has spread to nearby tissue or lymph nodes (locally advanced). Pidnarulex is an enzyme inhibitor that causes cell death and prevents tumor cell growth. Trastuzumab deruxtecan is in a class of medications called antibody-drug conjugates. It is composed of a monoclonal antibody, called trastuzumab, linked to a chemotherapy drug, called deruxtecan. Trastuzumab attaches to HER2 positive tumor cells in a targeted way and delivers deruxtecan to kill them. Giving pidnarulex in combination with trastuzumab deruxtecan may be safe, tolerable and/or effective in treating patients with metastatic, unresectable, or locally advanced HER2-expressing breast cancer or other solid tumors.

This phase I trial tests the safety, side effects, and best dose of pidnarulex in combination with trastuzumab deruxtecan in treating patients with breast cancer and other solid tumors that express varying levels of a protein called HER2 and that has spread from where it first started (primary site) to other places in the body (metastatic), that cannot be removed by surgery (unresectable), or that has spread to nearby tissue or lymph nodes (locally advanced). Pidnarulex is an enzyme inhibitor that causes cell death and prevents tumor cell growth. Trastuzumab deruxtecan is in a class of medications called antibody-drug conjugates. It is composed of a monoclonal antibody, called trastuzumab, linked to a chemotherapy drug, called deruxtecan. Trastuzumab attaches to HER2 positive tumor cells in a targeted way and delivers deruxtecan to kill them. Giving pidnarulex in combination with trastuzumab deruxtecan may be safe, tolerable and/or effective in treating patients with metastatic, unresectable, or locally advanced HER2-expressing breast cancer or other solid tumors.

This clinical trial tests the feasibility and utility of a biology guided therapy recommendations report to aid in determining treatment of hormone receptor positive breast cancer that may have spread from where it first started to nearby tissue, lymph nodes, or distant parts of the body may have spread from where it first started to nearby tissue, lymph nodes, or distant parts of the body (advanced), that cannot be removed by surgery (unresectable) or that has spread from where it first started (primary site) to other places in the body (metastatic). The biology guided therapy recommendations report is developed from testing a patients tumor tissue when they have progression to see what medications may work best and what medications the cancer may be resistant to based on their tumor biology. Patients and their doctor then receive that report with the suggested treatments. Receiving a biology guided therapy recommendations report may be a feasible and useable way to aid in treatment determination for hormone receptor positive advanced, unresectable or metastatic breast cancer.