A Study to Evaluate the Safety and PK of CRN04894 for the Treatment of Cushing's Syndrome

This study is testing a new drug called CRN04894 for people with Cushing's syndrome — a condition where the body produces too much cortisol (a stress hormone), caused by a tumor that overproduces ACTH, a hormone that signals the adrenal glands to make cortisol. **You may be eligible if:** - You are 18 or older (any gender) - You have been diagnosed with ACTH-dependent Cushing's syndrome (meaning your cortisol is too high because of a tumor producing excess ACTH) - Your Cushing's syndrome is currently active - You may be taking certain medications to lower cortisol (ketoconazole, osilodrostat, metyrapone, or cabergoline) but would need to stop them for a washout period before joining **You may NOT be eligible if:** - You are pregnant or breastfeeding - You have had both adrenal glands removed - You have a known cancer - You have a pituitary tumor very close to the optic nerve - You have recently taken the drug mitotane - You had unsuccessful Cushing's surgery within the past 6 weeks Talk to your doctor to see if this trial is right for you.