OtherEditorially reviewed · 30. Mai 2026

B7-33

Also known as B7-33, Single-Chain Relaxin, Relaxin-Mimetikum

not approvedEvidence · preclinical2 studies cited

Structure · schematic

Peptide chain of 25 amino acids · Sonstiges

Schematic representation of the amino acid chain — not a chemical structural formula. Each node represents one amino acid (shown truncated).

Research areas*

Recovery

* Contexts in which the peptide has been scientifically studied — not assured or recommended effects.

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Mechanism of action

  • B7-33 is a single-chain, simplified mimetic of the hormone relaxin-2.
  • Unlike natural two-chain relaxin it is more readily accessible synthetically and is said to act functionally selectively at the relaxin receptor RXFP1: primarily via anti-fibrotic (anti-scarring) signalling, with weaker activation of other cascades.
  • It is investigated in preclinical models of organ fibrosis and cardiac injury.
  • It is not an approved medicine.
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Research status

  • B7-33 has so far been studied exclusively preclinically.
  • Work describes B7-33 as a functionally selective RXFP1 agonist with cardioprotective and anti-fibrotic effects in cell and animal models.
  • Controlled human studies do not exist.
  • Safety and efficacy in humans are not demonstrated.

Evidence level

PreclinicalEarly clinicalEstablished
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Cited studies

  1. 2016
    A single-chain derivative of the relaxin hormone is a functionally selective agonist of the G protein-coupled receptor, RXFP1
  2. 2023
    The single-chain relaxin mimetic, B7-33, maintains the cardioprotective effects of relaxin
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Known risks

  • 01No human studies — safety profile entirely unknown
  • 02Interference with fibrotic/vascular signalling with unclear consequences
  • 03Interactions not characterised
  • 04Product quality cannot be verified from unapproved sources
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Frequently asked questions

What is B7-33?

B7-33 is a single-chain, simplified mimetic of the hormone relaxin-2.

What type of peptide is B7-33?

B7-33 belongs to the Other class.

Is B7-33 legal in Germany?

B7-33 is not approved as a medicine in Germany. Obtaining it outside clinical studies is legally problematic.

Where can I buy B7-33?

Peptica sells nothing and names no sources. B7-33 is "not approved" in Germany; obtaining unapproved substances outside clinical studies is illegal and carries quality and safety risks.

Is B7-33 banned in sport (WADA)?

B7-33 is currently not on the WADA Prohibited List.

What are the known risks of B7-33?

Documented risks include: No human studies — safety profile entirely unknown; Interference with fibrotic/vascular signalling with unclear consequences. This is not a complete safety assessment and not medical advice — see the risks section for the full list.

How well researched is B7-33?

The evidence is classified as “preclinical”. 2 studies are cited on this page.

Legal status

Germany

not approved

Austria

not approved

Switzerland

not approved

EU

not approved

USA

not approved

Canada

not approved

Legal status varies by country and can change. This is not legal advice.

Sources & methodology

  • 2 peer-reviewed studies cited, linked to PubMed where available.
  • Molecular data verified against PubChem and primary literature.
  • Editorial standard: no dosage guidance, no sources, evidence level stated explicitly.

Last editorially reviewed: 30 May 2026

Legal assessment

B7-33 is not approved as a medicine and is solely a preclinical research substance. Not on the WADA Prohibited List. Obtaining it as a research chemical carries considerable quality and safety risks.

Important notice

This site is intended solely for factual, scientifically oriented information about peptides. It does not constitute medical advice, does not replace a consultation with a doctor and contains no recommendations for use in humans.

This site does not sell any substances and names no sources for unapproved substances. For medical questions, please consult qualified medical professionals.

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Community notes

Note: These posts are user opinions and not medical advice. Posts containing dosages, therapeutic claims or purchase recommendations are removed. All entries are manually reviewed before publication.