This study is for people with a type of cancer called Platinum-Resistant Ovarian Cancer (PROC) that doesn't respond to usual treatments with platinum, a common cancer drug. The study looks at a medicine called INCB123667 to see if it’s safe and helps people with this cancer. Participants need to have a certain kind of cell activity, called Cyclin E1 overexpression, in their cancer cells. This means the cells grow too fast, which makes the cancer harder to treat.

• The study requires a biopsy, which is a small sample of tissue taken from your body.
• Participants should have had at least one, but no more than four, previous cancer treatments.
• The study will exclude people with certain types of ovarian cancer or other serious health issues.

If you join this study, you may have to stop any current treatments and follow the study plan. This could include regular doctor visits and tests to check your health and how the medicine is working. Be sure to ask the study team about any risks or benefits before deciding to join.