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HormoneFDA Approved

Macimorelin (Macrilen)

Oral
Written by Peptide Association Editorial TeamMedically reviewed by Ian Justl Ellis, MD, CPTLast reviewed Editorial policy

Overview

An orally bioavailable growth hormone secretagogue approved as a diagnostic agent for adult growth hormone deficiency (AGHD). Macimorelin stimulates GH release via GHS-R1a agonism, and the GH response to a standardized oral dose is used to confirm or exclude AGHD.

Mechanism of Action

It offers a simpler, better-tolerated alternative to the insulin tolerance test and GHRH-arginine test for GH deficiency diagnosis.

Research Summary & Key Findings

FDA-approved in 2017 as a diagnostic test for AGHD. Demonstrated 87% sensitivity and 96% specificity in clinical validation studies compared to the insulin tolerance test. Single oral dose produces measurable GH peak within 30-90 minutes. Well-tolerated with dysgeusia being the most common side effect (Garcia et al., J Clin Endocrinol Metab, 2018).

Clinical Status

FDA Approved

Macimorelin (Macrilen) has received FDA approval and is available for clinical use under appropriate medical supervision. Consult a qualified healthcare provider for prescribing information.

Administration Routes

Oral

References

Primary literature

Study-level citations for this compound are being verified against the primary sources before publication. The database queries above return the current indexed literature in the meantime.

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Disclaimer: This information is provided for educational and research purposes only. It is not intended as medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before starting any peptide therapy. The Peptide Association does not endorse or recommend any specific treatment protocol. See our editorial policy for how this content is produced and reviewed.