Metyrapone

Metopirone is indicated, in combination with other diagnostic tests, for the diagnosis of adrenal insufficiency in adult and pediatric patients. Metopirone is indicated, in combination with other diagnostic tests, for the diagnosis of adrenal insufficiency in adult and pediatric patients. ( 1 )

Capsules: Metopirone 250 mg soft gelatin, white to yellowish‑white, oblong, opaque, imprinted with "M01" on one side in red ink. Capsules: 250 mg ( 3 )

Metopirone is contraindicated in patients with adrenal cortical insufficiency or hypersensitivity to Metopirone or to any of its excipients. In patients with adrenal cortical insufficiency ( 4 ) Hypersensitivity to Metopirone or to any of its excipients ( 4 )

Adrenal Insufficiency: May induce acute adrenal insufficiency. Ability of adrenals to respond to exogenous ACTH should be demonstrated before Metopirone is employed as a test ( 5.1 ) Dizziness and Sedation: May cause dizziness and sedation. Patients should not drive or operate machinery until these effects have passed ( 5.2 )

5.1 Adrenal Insufficiency Metopirone may induce acute adrenal insufficiency in patients with reduced adrenal secretory capacity, as well as in patients with global pituitary insufficiency. The test should be performed in the hospital with close monitoring in case of suspected adrenal insufficiency. Ability of adrenals to respond to exogenous ACTH should be demonstrated before Metopirone is employed as a test. In the presence of hypo‑ or hyperthyroidism, response to the Metopirone test may be subnormal. If adrenocortical or anterior pituitary function is more severely compromised than indicated by the results of the test, Metopirone may trigger adrenal insufficiency. This can be corrected by giving appropriate doses of corticosteroids.

5.2 Dizziness and Sedation Metopirone may cause dizziness and sedation. Patients should not drive or operate machinery until these effects have passed.

The following adverse reactions associated with the use of Metopirone were identified in clinical trials or postmarketing reports. Because these reactions were reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Cardiovascular System: Hypotension Gastrointestinal System: Nausea, vomiting, abdominal discomfort or pain Central Nervous System: Headache, dizziness, sedation Dermatologic System: Allergic rash Hematologic System: Leukopenia, anemia, and/or thrombocytopenia Adverse reactions include: hypotension, nausea, vomiting, abdominal discomfort or pain, headache, dizziness, sedation, allergic rash, leukopenia, anemia, and/or thrombocytopenia. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Esteve Pharmaceuticals, S.A. at 1-888-306-6259 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

Anticonvulsants, psychotropic, hormone preparations, corticosteroids, antithyroid agents, cyproheptadine: may affect the results of the metyrapone test. ( 7.1 ) Acetaminophen: Avoid concomitant use with Metopirone. ( 7.2 )

7.1 Effect of Other Drugs on Metopirone Anticonvulsants, psychotropic drugs, hormone preparations, corticosteroids, antithyroid agents and cyproheptadine may affect the results of the Metopirone test. If these drugs cannot be withdrawn, the necessity of carrying out the Metopirone test should be reviewed.

7.2 Effect of Metopirone on Other Drugs Acetaminophen Metopirone inhibits the glucuronidation of acetaminophen, which may decrease elimination of acetaminophen and lead to increased risk of adverse reactions related to acetaminophen. Avoid concomitant use of Metopirone with acetaminophen.

8.1 Pregnancy Risk Summary Available data from published case series and reports on Metopirone use in pregnant females are insufficient to identify a drug-associated risk of major birth defects or miscarriage. Metyrapone crosses the placenta and may decrease fetal cortisol production (see Data ) . Animal reproductive studies have not been conducted with metyrapone. Metyrapone can decrease reproductive hormones by targeting adrenal androgenesis. Data Human Data The Metopirone test was administered to pregnant women in their second and third trimester of pregnancy and evidence was found that the fetal pituitary responded to the enzymatic block. Transplacental transfer of Metopirone has been shown in humans and the drug can impair the biosynthesis of fetal and placental steroids. There are a few published reports of low cortisol levels at birth in infants exposed in utero following chronic use of metyrapone in pregnant females.

8.2 Lactation Risk Summary Metyrapone and its active metabolite, metyrapol, are present in human milk. There are no available data on the effects of metyrapone on the breastfed infant or the effects on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for Metopirone and any potential adverse effects on the breastfed infant from Metopirone or from the underlying maternal condition.

8.4 Pediatric Use Metopirone is indicated, in combination with other diagnostic tests, for the diagnosis of adrenal insufficiency in pediatric patients [See Dosage and Administration (2.1) ].

8.5 Geriatric Use Clinical studies of Metopirone did not include sufficient numbers of patients 65 years of age and older to determine whether they respond differently from younger adult patients. Other reported clinical experience has not identified differences in responses between patients 65 years of age and older and younger adult patients.

8.6 Hepatic Impairment Patients with cirrhosis may have an impaired response to Metopirone.

The pharmacological effect of Metopirone is to reduce cortisol and corticosterone production by inhibiting the 11-beta-hydroxylation reaction in the adrenal cortex. Removal of the strong inhibitory feedback mechanism exerted by cortisol results in an increase in adrenocorticotropic hormone (ACTH) production by the pituitary. With continued blockade of the enzymatic steps leading to production of cortisol and corticosterone, there is a marked increase in adrenocortical secretion of their immediate precursors, 11-desoxycortisol and desoxycorticosterone, which are weak suppressors of ACTH release, and a corresponding elevation of these steroids in the plasma and of their metabolites in the urine. These metabolites are readily determined by measuring urinary 17‑hydroxycorticosteroids (17-OHCS) or 17-ketogenic steroids (17-KGS). Because of these actions, Metopirone is used as a diagnostic test, with urinary 17-OHCS measured as an index of pituitary ACTH responsiveness. Metopirone may also suppress biosynthesis of aldosterone, resulting in a mild natriuresis.