Semaglutide

What it is

Semaglutide is a peptide analogue that acts as a GLP-1 receptor agonist: it mimics the body's own hormone GLP-1, which plays a role in regulating blood glucose and satiety. It was developed as a medicine and is registered in Europe, the United States and many other countries.

Mechanism of action

Semaglutide acts on the GLP-1 receptor, which is involved in insulin release after a meal and in satiety signalling. The molecule is modified so that it breaks down more slowly than the body's own GLP-1, giving it a considerably longer half-life. This describes the point of action; it is not a statement about the outcome in any individual situation.

Research status

Semaglutide has been studied in large randomised clinical trials and is among the best-studied substances in its class. On the basis of that research it was registered as a medicine, with a package leaflet and an officially approved indication.

Regulatory status

Semaglutide is a registered medicine, available in the Netherlands on prescription only, under brand names such as Ozempic, Wegovy and Rybelsus. The EMA (Europe) and the FDA (United States) have assessed and approved it.

An important distinction. The approved medicine is a controlled product with a known composition, a package leaflet and supervised manufacturing. Material traded outside that chain as "research semaglutide" is not equivalent: composition, purity, sterility and provenance are not guaranteed. See Quality & provenance.

What remains unknown

For the registered medicine, efficacy and safety have been studied within the approved indication; a physician weighs this per patient, including side effects and interactions. For unregulated material that certainty does not exist — there, even the presence of the stated quantity of substance is unverified.