A Study of ATR-101 for the Treatment of Endogenous Cushing's Syndrome

A Phase 2 Randomized, Double-Blind, Placebo-Controlled Study of ATR-101 for the Treatment of Cushing's Syndrome

This is a Phase 2 multicenter, randomized, double-blind, placebo controlled study of ATR-101 to evaluate the efficacy and safety of orally-administered ATR-101 in adults with endogenous Cushing's syndrome. Following wash-out (if needed), all eligible subjects will enter an open-label intra-subject dose-escalation period of 8 weeks' duration, followed either by a double-blind randomized withdrawal period of 4 weeks' duration (if the subject meets randomization criteria) or by an additional open label dosing period of 4 weeks' duration (if the subject does not meet randomization criteria).It is anticipated that the overall duration of the study per subject will range from approximately 16-22 weeks.

Inclusion Criteria:

• Confirmed diagnosis of endogenous Cushing's syndrome
• Baseline UFC 1.3 to 10 × upper limit of normal (ULN)
• If previous pituitary surgery, participants must be at least 3 months since surgery at the time of screening
• BMI between 18 and 60 kg/m2, inclusive

Exclusion Criteria:

• Pseudo-Cushing's syndrome, cyclic Cushing's syndrome or current iatrogenic Cushing's syndrome
• Candidates for surgical treatment of Cushing's syndrome, unless surgery is not anticipated to occur during the study
• Normal late night salivary cortisol or 24-hr urine free cortisol
• Radiotherapy of the pituitary within 6 months