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All peptides
CardiovascularInvestigational

Serelaxin (Relaxin-2)

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

Overview

Serelaxin is a recombinant form of human relaxin-2, a naturally occurring peptide hormone composed of two chains linked by disulfide bonds. It acts via the relaxin family peptide receptor 1 (RXFP1) to promote vasodilation, inhibit fibrosis, and modulate hemodynamics.

Mechanism of Action

The therapeutic rationale targets acute heart failure by improving renal perfusion and reducing vascular resistance.

Research Summary & Key Findings

The RELAX-AHF trial (Lancet, 2013) demonstrated improved dyspnea and reduced 180-day mortality in acute heart failure patients, but the subsequent RELAX-AHF-2 trial (JAMA, 2017) failed to confirm a mortality or cardiovascular event benefit. The FDA did not approve serelaxin, and further development was discontinued.

Clinical Status

Investigational

Serelaxin (Relaxin-2) is in the investigational stage. While preclinical and early-phase data exist, it has not received regulatory approval for clinical use in the United States.

Administration Routes

Intravenous

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.

Related Peptides in Cardiovascular

No lawful pathway today

Serelaxin (Relaxin-2) is not FDA-approved and does not currently have a lawful prescription or compounding pathway in the United States, so there is nothing for us to sell you here and no consultation to book. That can change: eight peptides moved back to a lawful pathway in February 2026.

Tell me if the status changes

One email, only if this compound's regulatory standing actually moves. Not a newsletter, not a sales sequence.

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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.