This is a multi-centre, observational, non-comparative, retrospective cohort study designed to evaluate the long-term safety and effectiveness of osilodrostat in non-CD CS patients. Patients treated with oral osilodrostat regardless of the duration of their treatment will be followed retrospectively for up to 36 months after initiating osilodrostat.

Inclusion Criteria:

1. Male and female patients ≥18 years old with diagnosis of CS, except for CD (i.e., an aetiology of adrenal adenoma, adrenocortical carcinoma, adrenal hyperplasia, or ectopic adrenocorticotropic hormone secretion). Patients should have a contemporaneously documented diagnosis of CS as per effective guidelines.
2. Patients treated with osilodrostat between April 2019 and study start date as part of ATU programme or commercialisation.

Exclusion Criteria:

1. Patients who participated in a clinical trial anytime during the study period.
2. Patients with Pseudo-Cushing's syndrome, cyclic CS, or iatrogenic CS.

The study population will consist of patients with non-CD CS. Patients meeting eligibility criteria will be retrospectively identified and included in the study by site investigators based on a review of medical records at site. Site policies and local regulations regarding patient consent (NOL) will be followed. All eligible patients identified at a site between April 2019 and study start date and consenting to be part of the study will be included.

For 36 months (study period) and for at least 12 weeks of retrospective follow-up (follow-up for each patient was variable, and based on the clinical judgement of the physicians at the investigative sites).