Legal status · United Kingdom
Is B7-33 legal in the United Kingdom?
No. B7-33 is not an approved medicine in the United Kingdom; its classification is "Unlicensed medicine; supply for human use is unlawful". Nothing containing it is authorized for any use in people. Vials labeled "for research use only" are not exempt: that label does not make human use lawful. Human evidence: Preliminary.
B7-33 in the United Kingdom at a glance
| Classification | Unlicensed medicine; supply for human use is unlawful |
|---|---|
| MHRA approval status | Not approved by MHRA |
| Evidence level | Preliminary (research strength: Preliminary) |
| Reviewed | Sep 2026 |
Classification and note come from the B7-33 profile, checked against Medicines and Healthcare products Regulatory Agency (MHRA) listings at the reviewed date.
What this means
- 01
No product containing B7-33 is approved by MHRA for any use in the United Kingdom, so nothing on the market is authorized for people.
- 02
"Research use only" is a vendor label, not a legal category that permits human use. It does not exempt a product from medicines law.
- 03
Importing, supplying or promoting it for human use can fall under medicines legislation in the United Kingdom. This page is general information, not legal advice.
What B7-33 is
A simplified relaxin analog that activates the RXFP1 receptor with a bias toward anti-fibrotic signaling; animal and cell data only.
Relaxin is a hormone with anti-fibrotic effects but is hard to manufacture. B7-33 is a single-chain derivative that reproduced relaxin's anti-fibrotic actions in animal models of heart and lung fibrosis without the receptor-desensitizing cAMP signaling.
Mechanism: Functionally selective RXFP1 agonism biased toward pERK-mediated anti-fibrotic signaling.
Regulatory history: Not approved
How MHRA treats this kind of product
Licenses medicines for the UK market. A compound without a marketing authorisation is an unlicensed medicine, which can only lawfully be supplied for human use through a prescriber under the specials scheme, not sold as a research product.
The classification above is the The Longevity Archive reading of Medicines and Healthcare products Regulatory Agency listings for B7-33 at the reviewed date, not a legal opinion. Rules change, and importing, prescribing and possessing a compound can each be treated differently. Check the regulator directly before acting on anything here.
B7-33 in other countries
Frequently asked questions
Is B7-33 legal in the United Kingdom?
No. B7-33 is not an approved medicine in the United Kingdom; its classification is "Unlicensed medicine; supply for human use is unlawful". Nothing containing it is authorized for any use in people. Vials labeled "for research use only" are not exempt: that label does not make human use lawful. Human evidence: Preliminary.
Can I buy B7-33 in the United Kingdom?
No approved product exists to buy. In the United Kingdom B7-33 is classified as "Unlicensed medicine; supply for human use is unlawful", so there is no licensed pharmacy product. Vendors selling it "for research use only" are not selling it for human use, and that label does not change its legal status. This site does not list or recommend vendors.
Is B7-33 MHRA approved?
No. In the United Kingdom B7-33 is classified as "Unlicensed medicine; supply for human use is unlawful", which is not a MHRA marketing approval. For comparison, the US FDA status is: Not approved. Evidence level: Preliminary.
Related compounds in the United Kingdom
Full research profile
Mechanism, cited studies, FDA status and the full legal summary for B7-33 live on its compound profile.
B7-33 profileThis page is general information about the regulatory status of B7-33 in the United Kingdom, current as of Sep 2026. It is not legal advice, and classifications change; check Medicines and Healthcare products Regulatory Agency directly or consult a lawyer for a specific situation. Educational use only. This database summarizes published research. It is not medical advice and contains no dosing protocols or recommendations for personal use. The Longevity Archive has no vendor relationships and does not recommend where to buy anything.