Is Relaxin-2 legal in the United Kingdom?

The pregnancy hormone that opens up blood flow. A drug version, serelaxin, was tested in 1,161 people with sudden heart failure, and there were 42 deaths by six months on the drug against 65 on a dummy drip. But that was a side question. The bigger follow-up in 6,545 people found heart deaths of 8.7 percent on the drug and 8.9 percent without it. Serelaxin was never approved and work on it for heart failure stopped.

Relaxin-2 is a hormone made of two linked chains, from the same family as insulin. The ovary and the placenta make it.

How it works: Relaxin-2 works through a receptor called RXFP1. It widens blood vessels across the body, makes the heart pump more, sends more blood to the kidneys and makes arteries more stretchy.

Approval history: Relaxin-2 is a hormone the body makes. Serelaxin, a lab-made copy of it, is not approved by the FDA or any other regulator. It drew attention after the RELAX-AHF result. But the larger follow-up study, RELAX-AHF-2, missed both of its main goals, and work on it for sudden heart failure was stopped.

Licenses medicines for sale in the UK. A compound without a licence to be sold (a marketing authorisation) is an unlicensed medicine. The law only lets it reach people through a prescriber, under the specials scheme (unlicensed medicines made for one patient's needs). It cannot be sold as a research product.

The legal category above is how The Longevity Archive reads Medicines and Healthcare products Regulatory Agency listings for Relaxin-2 on the reviewed date. It is not a legal opinion. Rules change. Bringing a compound into the country, prescribing it and owning it can each be treated differently. Check with the agency before you act on anything here.

Check MHRA directly

Whether Relaxin-2 is banned in sport is set by the World Anti-Doping Code and by military rules, not by its legal status in the United Kingdom. Before you compete or get tested, look up Relaxin-2 by name on the Prohibited List, or look up a named product in Global DRO. Under the World Anti-Doping Code, category S0 bans, at all times, any drug-like substance that meets two tests. No other section of the List covers it. And no government health regulator anywhere has a current approval for it as a treatment in people. Many substances that are approved somewhere are banned by name in another section. So approval does not mean a substance is allowed in sport.

• WADA Prohibited List
• Global DRO (check a named product)
• USADA (US athletes)
• Operation Supplement Safety (US service members)

The rules you compete or serve under decide this, not this page.