Study to Evaluate CORT125134 in Participants With Cushing's Syndrome

Phase 2 Study of the Safety and Efficacy of CORT125134 in the Treatment of Endogenous Cushing's Syndrome

Cushing's syndrome is a relatively rare disorder caused by prolonged exposure to high levels of the glucocorticoid hormone cortisol. Cushing's syndrome may result from elevated endogenous or exogenous sources of cortisol. Endogenous Cushing's syndrome resulting from cortisol overproduction by the adrenal glands is the subject of this protocol.

Patients with exogenous Cushing's syndrome, which develops as a side effect of chronic administration of high doses of glucocorticoids, were not eligible for enrollment in this study.

The purpose of this study was to evaluate the safety and efficacy of CORT125134 for treatment of endogenous Cushing's syndrome. The multicenter study was conducted in the United States and in Europe.

This was a Phase 2, open-label study with two dose groups, each with a two-step dose escalation, designed to evaluate the safety and efficacy of CORT125134 for the treatment of endogenous Cushing's syndrome. CORT125134 was administered orally once daily for 16 weeks with dose escalations occurring every 4 weeks.

Pharmacokinetics (PK) profiles were generated at every dose level. A data review committee reviewed PK and safety data and recommended the final plan for dose escalation in Group 2.

Inclusion Criteria:

1. Has a confirmed diagnosis of endogenous Cushing's syndrome.

2. Requires medical treatment of hypercortisolemia.

3. Meets at least one of the following criteria:

   1. Has type 2 diabetes mellitus.
   2. Has impaired glucose tolerance.
   3. Has hypertension.

Exclusion Criteria:

1. Has non-endogenous source of hypercortisolemia
2. Has uncontrolled, clinically significant hypothyroidism or hyperthyroidism
3. Has poorly controlled hypertension
4. Has Stage ≥ 4 renal failure