 Up to 50 subjects will receive mifepristone daily. Subjects completing 24 weeks of mifepristone treatment under Corcept protocol C1073-400 NCT00569582 will be eligible to continue treatment for an additional 1 year. Assessments of safety, as evaluated by physical examinations, vital signs, laboratory tests and adverse events, will be made. Persistence of improvement in response to mifepristone treatment will also be evaluated during this extension study by assessing the continued or sustained improvement in the signs and symptoms of Cushings syndrome. 