Testing a New Drug, ZEN003694, With Chemotherapy (Abemaciclib), for People With Advanced or Inoperable Breast Cancer and Other Solid Tumors

About the Study

This clinical trial is studying whether the combination of two investigational drugs — ZEN003694 (also known as ZEN-3694) and abemaciclib — can be given safely together and what dose should be used in future trials.

• ZEN003694 is an experimental drug that targets proteins involved in cancer cell growth.

• Abemaciclib is a drug that may slow cancer cell division by blocking key enzymes involved in cell growth.

Researchers also want to gather early information about whether this drug combination may help shrink or control cancer in people whose tumors have spread or cannot be removed by surgery.

This Phase 1 trial focuses first on safety and side effects and determining the best dose for future studies.

What the Study Involves

If a person joins this trial:

• They will receive both drugs by mouth (oral medication) in repeated treatment cycles.
• Treatment continues in 28-day cycles as long as it is safe and the cancer has not progressed.
• While on the study, participants will have blood tests, imaging scans (like CT or MRI), and tumor biopsies to monitor how the drugs act and how the cancer responds.
• After stopping treatment, participants are followed for regular check-ins for several years to monitor long-term safety and outcomes.

This study is open to:

• People aged 12 years and older.
• People with advanced solid tumors that have spread (metastatic) or cannot be surgically removed (unresectable), including NUT carcinoma.
• People whose disease cannot be cured or controlled with standard treatments or for whom standard options are no longer effective.

This study is not open to:

• People under 12 years of age.
• People with cancers that can be treated effectively with standard therapies.
• People who have serious uncontrolled medical conditions that could interfere with study treatment or safety.
• People who are pregnant.