FDA Approved Growth Hormone Axis

Corticorelin

also known as: Acthrel, human CRH, ovine CRH, corticorelin ovine triflutate, CRF

Ferring Pharmaceuticals' synthetic ovine CRH (Acthrel) — FDA-approved diagnostic peptide used to distinguish pituitary Cushing disease from ectopic ACTH secretion via inferior petrosal sinus sampling or peripheral ACTH/cortisol response testing.

Synthetic corticotropin-releasing hormone (CRH, also called corticotropin-releasing factor, CRF) — a 41-amino-acid hypothalamic releasing peptide. The ovine sequence is marketed in the United States as Acthrel (Ferring Pharmaceuticals) as a diagnostic agent to evaluate the pituitary-adrenal axis. Principal clinical use is distinguishing pituitary Cushing disease from ectopic ACTH secretion during inferior petrosal sinus sampling (IPSS) or during peripheral ACTH/cortisol response testing — pituitary adenomas respond to CRH with a brisk ACTH rise, while ectopic ACTH-secreting tumors typically do not.

Mechanism of action

Binds corticotropin-releasing hormone receptor type 1 (CRHR1) on anterior pituitary corticotrophs, stimulating ACTH release and, downstream, cortisol secretion. In Cushing diagnostics, a robust ACTH response indicates intact pituitary corticotroph tissue (characteristic of pituitary microadenoma), while blunted or absent response during IPSS with peripheral ACTH rise suggests an ectopic ACTH source.

Primary uses

  • Diagnostic: differential diagnosis of Cushing syndrome (pituitary vs ectopic ACTH)

Typical dosing

1 mcg/kg single diagnostic dose (intravenous bolus)

Administered during inferior petrosal sinus sampling or as part of a peripheral CRH stimulation test. Central-to-peripheral ACTH gradient interpretation follows standard endocrinology protocols.

Regulatory status

FDA-approved as Acthrel (corticorelin ovine triflutate, Ferring Pharmaceuticals) for use in the differential diagnosis of Cushing syndrome. Single diagnostic use; not indicated for therapy.

References

  1. [fda-pi] Acthrel (corticorelin ovine triflutate) Prescribing Information. Ferring Pharmaceuticals.
  2. [review] Nieman LK, et al. "The diagnosis of Cushing's syndrome: an Endocrine Society clinical practice guideline." J Clin Endocrinol Metab, 2008;93:1526-1540.

Related peptides

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Sermorelin

The N-terminal 29 amino acids of native GHRH — a former FDA-approved diagnostic and pediatric GH-deficiency therapy, now widely compounded for adult anti-aging protocols.

Protirelin

Synthetic TRH (thyrotropin-releasing hormone) — historically FDA-approved in the US as Thypinone, Relefact TRH, and Thyrel TRH for TSH stimulation testing; US commercial supply has lapsed and TRH testing is now rarely performed with the widespread availability of sensitive third-generation TSH assays.

Gonadorelin

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Disclaimer

This entry is for educational purposes only and does not constitute medical advice. Dosing information reflects published regulatory or research data and is not a recommendation. Many compounds described here are not approved for human use in the United States. Consult a licensed medical professional before considering any peptide therapy.