Study to Determine the Prevalence of Hypercortisolism in Patients With Type 2 Diabetes and Treatment With Korlym® (Mifepristone) (CATALYST)

Inclusion Criteria: Has difficult to control T2D (HbA1c ≥7.5% and ≤11.5%) based on HbA1c performed at screening. AND Taking 3 or more anti-hyperglycemic drugs. OR Taking insulin and other anti-hyperglycemic drugs. OR Taking 2 or more anti-hyperglycemic drugs AND a.) the presence of 1 or more micro-vascular or macro-vascular complication (retinopathy, diabetic nephropathy and chronic kidney disease, diabetic neuropathy, atherosclerotic heart disease with diabetes); AND/OR b.) concomitant hypertension requiring 2 or more anti-hypertension medications. Exclusion Criteria: Has type 1 diabetes mellitus. New-onset diabetes less than 1 year. Systemic glucocorticoid medications exposure (excluding inhalers or topical) within 3 months of screening. Is pregnant or lactating. For women of childbearing potential, have a positive pregnancy test before dexamethasone administration. A woman of childbearing potential includes all women <50 years old, women whose surgical sterilization was performed <6 months ago, and women who have had a menstrual period in the last 12 months. On hemodialysis or has end-stage renal disease. Has severe untreated sleep apnea as judged by the Investigator. Has excessive alcohol consumption (>14 units/week for male, >7 units/week for female) as judged by the Investigator. Has severe psychiatric illness by history (such as schizophrenia or dementia) as judged by the Investigator. Has severe medical or surgical illness as judged by the Investigator. Is a night shift worker, i.e., is awake from approximately 11 PM to 7 AM. Has taken any investigational drug within 4 weeks prior to screening, or within less than 5 times the drug's half-life, whichever is longer. Has had the diagnosis of Cushing syndrome or has used or plans to use any of the following treatments for Cushing syndrome: - Mifepristone, metyrapone, osilodrostat, ketoconazole, fluconazole, aminoglutethimide, etomidate, octreotide, larazotide, pasireotide, long-acting octreotide or pasireotide. Has a history of hypersensitivity or severe reaction to dexamethasone