Mazdutide Peptide

Nature got to the dual agonist first. It just never told anybody.

Mazdutide (IBI362, LY3305677) is a 34-amino-acid oxyntomodulin analogue acting as a dual glucagon receptor and GLP-1 receptor agonist, with an Aib substitution at position 2, a C-terminal amide, and an acyl chain on Lys20. The WHO INN record gives a molecular formula of C210H322N46O67 and a molecular weight of approximately 4563, CAS 2259884-03-0; it is approved by China's NMPA and by no other regulatory authority.

Here's a slightly annoying fact if you're a medicinal chemist.

Everybody has spent years building molecules that pull two receptors at once. Clever work, real engineering, genuine achievement.

It's called oxyntomodulin. It comes off the same precursor protein as GLP-1, it is a perfectly ordinary human peptide, and it engages both the GLP-1 receptor and the glucagon receptor without anybody designing it to.

Mazdutide is an analogue of that.

So the job here wasn't invention. It was taking something nature already built and fixing the part nature had no reason to care about, which is how long it lasts.

Native oxyntomodulin clears in minutes. Nature is not optimising for weekly dosing.

Two receptors, one peptide, and no chemist required for the original draft.

Alright. Proglucagon is one precursor protein that gets cut into different pieces depending on which tissue is doing the cutting.

Cut it one way, you get glucagon. Cut it another way, you get GLP-1. Cut it a third way and you get oxyntomodulin, which happens to talk to both receptors.

That's a genuinely elegant bit of biology and it is also the whole basis of this molecule.

This analogue takes that natural dual-acting peptide and does the standard two things: stabilise it against the enzymes that clear it, and add a lipid so it binds albumin and sticks around.

Here's the honest part. Being derived from a human peptide sounds reassuring and it is not an argument about anything.

Plenty of things your body makes are unpleasant in the wrong amount, and a modified version of a natural molecule is still a modified molecule with its own behaviour.

Natural origin is a fact about where it came from. It is not a safety claim, and we are not making one.

Approved in one country, unapproved everywhere else, and unusually easy to misread because of it.

This one is easy to misread, so here is the shape of it plainly.

It holds regulatory approval in China and nowhere else. Not Canada.

Not the United States. Not Europe.

That matters for reading the literature, because a good deal of the clinical work sits with one sponsor in one jurisdiction, which is a narrower base than the multi-region programmes behind some of its neighbours on this shelf.

It is not a criticism of the work. It is a note about how much independent replication exists, which is a different question and the one people forget to ask.

Approved somewhere, unapproved here, and thinner outside its home programme than the headline suggests.

Approved in China only. Xinermei is a real approved product in China. Mazdutide has no FDA, EMA or Health Canada authorisation, and what we ship is a research material rather than any approved drug product.

The anti-doping answer is unresolved. Mazdutide isn't named on the 2026 WADA list, but S0 catches unapproved substances and WADA hasn't said whether an NMPA approval counts. Anyone in tested sport should ask their anti-doping authority directly rather than guess.

Canadian stock, ships from BC. Held in Canada so it isn't sitting in a customs queue while the cold chain degrades. Research use only, and not for any human or veterinary application.