Overview
B7-33 is a functionally selective, single-chain synthetic peptide mimetic derived from the human peptide hormone relaxin-2.
What problem it targets: It is engineered to treat fibrotic diseases, heart failure, organ scarring (cardiac, pulmonary, renal, and vascular fibrosis), and pathological tissue stiffening.
What It Does
• Selectively activates RXFP1 receptors: Triggers the beneficial pERK1/2 anti-fibrotic signaling cascade without activating the cAMP pathways that cause unwanted blood pressure drops or tumor-growth risks.
• Breaks down pathological collagen scars: Upregulates matrix metalloproteinases (MMPs), enzymes that systematically dissolve excess, rigid collagen fibers in scarred organs.
• Promotes microvascular health: Stimulates tissue blood flow and blunts chronic inflammation that drives ongoing organ fibrosis and stiffness.
• Realistic expectations: In preclinical heart and lung models, B7-33 reduced established fibrosis by over 50%. It is designed as an organ-protective anti-scarring agent, not a performance stimulant.
Reconstitution
| Vial size | BAC water / Solvent | Concentration |
|---|---|---|
| 2 mg | + 0.4 mL | 5 mg/mL |
| 10 mg | + 2 mL | 5 mg/mL |
Protocol
| Phase | Frequency | Dose | Units (2 mg/mL) | Notes |
|---|---|---|---|---|
| Research-derived | Daily | 100–500 mcg | 5–25u | SubQ. Animal-study-derived range only, no validated human dose or safety margin. |
| Off | variable | – | – | No established cycle, preclinical compound. Caution: B7-33’s entire evidence base is animal data. There is no clinically validated protocol, no approved human route, and no established safety margin. Doses here are research-derived and included for completeness only. Relaxin signaling affects the vasculature and connective tissue broadly. By sex: Relaxin analog, contraindicated in pregnancy (relaxin acts on the reproductive tract). Otherwise unisex; entirely preclinical. |
Handling & Stacking
- Freeze-dried: -4°F.
- Reconstituted: 36–46°F.
- Best used within ~2–4 weeks, kept cold (structure-based estimate, no published data); that is close to the 28- day sterility limit, so use whichever comes first.
- Unknown in humans.
- Animal data suggest anti-fibrotic, organ-protective effects; not demonstrated in people.
- Supply math 2mg → ~6 vials | 10mg → ~2 vials (4-wk @ 400 mcg/day, research-derived, not a recommendation)
