Cortrosyn

CORTROSYN is indicated, in combination with other diagnostic tests, for use as a diagnostic agent in the screening of adrenocortical insufficiency in adults and pediatric patients. CORTROSYN is an adrenocorticotropin hormone indicated, in combination with other diagnostic tests, for use as a diagnostic agent in the screening of adrenocortical insufficiency in adults and pediatric patients. (1)

For Injection: 0.25 mg of cosyntropin as a lyophilized powder in a single-dose vial for reconstitution. For injection: 0.25 mg of cosyntropin as a lyophilized powder in single-dose vial for reconstitution (3)

CORTROSYN is contraindicated in patients with a history of hypersensitivity to cosyntropin or to any excipients of CORTROSYN. Reactions have included anaphylaxis [see Warnings and Precautions (5.1)]. CORTROSYN is contraindicated in patients with a history of hypersensitivity to cosyntropin or to any excipients of CORTROSYN. Reactions have included anaphylaxis. (4, 5.1)

5.1 Hypersensitivity to CORTROSYN Injection CORTROSYN injection hypersensitivity reactions including anaphylaxis have been reported. Monitor patients for hypersensitivity reactions and treat as needed.

5.2 Diagnostic Inaccuracies Cortisol levels and subsequent diagnosis of adrenocortical insufficiency following CORTROSYN administration may be inaccurate if patients are on certain medications because of their effect on cortisol or cortisol binding globulin levels. Glucocorticoids and spironolactone may result in falsely elevated cortisol levels. Stop these drugs on the day of CORTROSYN testing. Long-acting glucocorticoids may need to be stopped for a longer period before CORTROSYN testing [see Dosage and Administration (2.1) and Drug Interactions (7)]. Estrogen-containing drugs increase cortisol binding globulin levels which can increase plasma total cortisol levels. To obtain accurate plasma total cortisol levels, stop estrogen containing drugs four to six weeks before CORTROSYN testing to allow cortisol binding globulin levels to return to levels within the reference range [see Dosage and Administration (2.1) and Drug Interactions (7)]. Alternatively, concomitant measurement of cortisol binding globulin at the time of testing can be done; if cortisol binding globulin levels are elevated, plasma total cortisol levels are considered inaccurate. Any condition that elevates or lowers cortisol binding globulin levels may increase or decrease plasma total cortisol levels, respectively. Cortisol binding globulin levels can be low in cirrhosis or nephrotic syndrome. Measure cortisol binding globulin levels as necessary to ensure accuracy of interpretation of plasma total cortisol levels. Hypersensitivity: reactions including anaphylaxis have been reported. Monitor patients for hypersensitivity reactions and treat as needed. (5.1) Diagnostic Inaccuracies: Cortisol levels and subsequent diagnosis of adrenocortical insufficiency following CORTROSYN administration may be inaccurate if patients are on certain medications because of their effect on cortisol or cortisol binding globulin levels. Any condition that elevates or lowers cortisol binding globulin levels may increase or decrease plasma total cortisol levels, respectively. (2.1, 5.2, 7)

Because adverse reactions are 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. The following adverse reactions have been identified during post approval use of CORTROSYN: anaphylactic reaction bradycardia tachycardia hypertension peripheral edema rash Most common adverse reactions are: anaphylactic reaction, bradycardia, tachycardia, hypertension, peripheral edema, and rash (6) To report SUSPECTED ADVERSE REACTIONS, contact Amphastar Pharmaceuticals, Inc. at 1-800-423-4136 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

7.1 Drug Effects on Plasma Cortisol Levels Accuracy of the test results can be affected by concomitant medications. Plasma cortisol levels and subsequent diagnosis of adrenocortical insufficiency following CORTROSYN administration may be inaccurate if patients are on certain medications because of their effect on cortisol or cortisol binding globulin levels [see Dosage and Administration (2.1) and Warnings and Precautions (5.2)]. Glucocorticoids and spironolactone: May falsely elevate plasma cortisol levels. Stop these drugs on the day of CORTROSYN testing. Long-acting glucocorticoids may need to be stopped for a longer period before CORTROSYN testing. Estrogen: May elevate plasma total cortisol levels. Stop estrogen containing drugs 4 to 6 weeks before CORTROSYN testing to allow cortisol binding globulin levels to return to levels within the reference range. Alternatively, concomitant measurement of cortisol binding globulin at the time of testing can be done; if cortisol binding globulin levels are elevated, plasma total cortisol levels are considered inaccurate. Drug effects on plasma cortisol levels: ◦ Accuracy of the test results can be affected by concomitant medications.◦ Glucocorticoids and spironolactone: May falsely elevate plasma cortisol levels. Stop these drugs on day of CORTROSYN testing. Long-acting glucocorticoids may need to be stopped for a longer period before CORTROSYN testing. (7)◦ Estrogen: May elevate plasma total cortisol levels. Stop estrogen containing drugs 4 to 6 weeks before CORTROSYN testing. (7) See 17 for PATIENT COUNSELING INFORMATION Revised 12/2023

8.1 Pregnancy Risk Summary Available data from case reports over decades of use with cosyntropin during pregnancy have not identified an increased risk of major birth defects, miscarriage or adverse maternal or fetal outcomes. Unidentified adrenal insufficiency can result in adverse maternal or fetal outcomes (see Clinical Considerations). The background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk for major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Clinical Considerations Disease-associated maternal and/or embryo/fetal risk Unidentified adrenal insufficiency during pregnancy can result in maternal and/or fetal death; therefore, the diagnosis of suspected adrenal insufficiency during pregnancy should not be delayed.

8.2 Lactation Risk Summary There are no data on the presence of cosyntropin in human milk, the effects 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 CORTROSYN and any potential adverse effects on the breastfed infant from CORTROSYN or from the underlying maternal condition.

8.4 Pediatric Use CORTROSYN is approved for use in pediatric patients [see Dosage and Administration (2.3)].