Validation of Macimorelin as a Test for Adult Growth Hormone Deficiency

Inclusion Criteria: * Suspected growth hormone deficiency (GHD), based on either of the following: * structural hypothalamic or pituitary disease, or * surgery or irradiation in these areas, or * head trauma as an adult, or * evidence of other pituitary hormone deficiencies, or * idiopathic childhood onset GHD (without known hypothalamic or pituitary lesion or injury). * Healthy\* control subjects, matching a 'high likelihood GHD' subjects Exclusion Criteria: * GH therapy within 1 month prior to anticipated first GHST within this trial (within 3 months in case of long-acting GH formulation). * GHST within 7 days prior to the anticipated first test day within the trial. * Subjects with a medical history and clinical signs of a not adequately treated thyroid dysfunction or subjects who had a change in thyroid therapy within 30 days prior to anticipated first test day within the trial. * Untreated hypogonadism or not on a stable substitution treatment within 30 days prior to anticipated first test day within the trial. * Treatment with drugs directly affecting the pituitary secretion of somatotropin (e.g. somatostatin analogues, clonidine, levodopa, and dopamine agonists) or provoking the release of somatostatin; antimuscarinic agents (atropine). * Concomitant use of a CYP3A4 inducer (e.g., carbamazepine, phenobarbital, phenytoin, pioglitazone, rifabutin, rifampin, St. John's Wort). * Medical history of ongoing clinically symptomatic severe psychiatric disorders. *…