title: Mifepristone Improves Octreotide Efficacy in Resistant Ectopic Cushing's Syndrome.
abstract: A 30-year-old Caucasian man presented with severe Cushing's syndrome (CS) resulting from ectopic adrenocorticotropin syndrome (EAS) from a metastatic pancreatic neuroendocrine tumor. The patient remained hypercortisolemic despite treatment with steroidogenesis inhibitors, chemotherapy, and octreotide long-acting release (LAR) and was enrolled in a 24-week, phase 3 clinical trial of mifepristone for inoperable hypercortisolemia. After mifepristone was added to ongoing octreotide LAR treatment, EAS symptoms essentially resolved. Cortisol decreased dramatically, despite mifepristone's competitive glucocorticoid receptor antagonist effects. The clinical and biochemical effects reversed upon mifepristone discontinuation despite the continued use of octreotide LAR therapy. Substantial improvement in octreotide LAR efficacy with mifepristone use was noted in this patient with ectopic CS, consistent with upregulation of somatostatin receptors previously downregulated by hypercortisolemia.
authors.affiliation: Corcept Therapeutics, 149 Commonwealth Drive, Menlo Park, CA 94025, USA.
authors.forename: Andreas G
authors.initials: AG
authors.lastname: Moraitis
authors.affiliation: Division of Metabolism, Diabetes, and Endocrinology, Department of Internal Medicine, University of Michigan, 1150 West Medical Center Drive, Ann Arbor, MI 48109, USA.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Auchus