Two names, two receptor footprints

Semaglutide is a single agonist. It reaches one receptor, GLP-1, the incretin most studied for its role in appetite and glucose signalling. It is the molecule behind the widely known Ozempic and Wegovy brands, and in Australia it is a registered prescription medicine.

Retatrutide is a triple agonist. It reaches three receptors, GLP-1, GIP, and the glucagon receptor. That wider footprint is the entire distinction between the two, and it is why retatrutide is the compound most closely watched in current metabolic research.

Single agonist versus triple agonist

The class is defined by receptor reach, so the clearest way to compare these two is to line up exactly what each one touches.

• SemaglutideGLP-1 only. One incretin pathway, the most established single-receptor target in the class.
• RetatrutideGLP-1 plus GIP plus glucagon. Two incretin pathways and the glucagon pathway that sits at the centre of energy-expenditure and lipid-handling research.
• What the reach changesMore receptors means a broader research question, not an automatic upgrade. The glucagon pathway adds a dimension a single agonist does not address.

Availability in Australia

Semaglutide is a scheduled prescription medicine in Australia, so we do not offer it. Where it appears in a comparison like this, it is as the reference point for the single-agonist end of the class, not a product we sell.

At Polaris Research we stock retatrutide as research-grade material in both 10mg and 20mg vials. For researchers who want the widest receptor reach in the current literature, retatrutide is the compound we carry, and the two vial sizes let you match quantity to the scope of the work. If you have read our Retatrutide vs Tirzepatide comparison, this is the same axis extended: semaglutide reaches one receptor, tirzepatide reaches two, and retatrutide reaches three.

Which researchers pick which

The choice follows the research question. If the work is narrowly about the GLP-1 pathway on its own, semaglutide is the reference single agonist, but that is a clinical, prescription context rather than a research-supply one. If the question extends across the incretin and glucagon pathways together, retatrutide is the compound that reaches all three.

For most laboratory work framing the metabolic pathways broadly, the triple agonist is the more informative starting point, which is why retatrutide draws the majority of current interest. Choose the 10mg vial for shorter studies and the 20mg for longer or higher-volume work.

Certificates, handling, and delivery

Retatrutide ships as lyophilised powder with an independently verified Certificate of Analysis (COA) confirming identity and purity against the batch number on the label. Reconstitute with Bacteriostatic Water added gently down the wall of the vial, never onto the powder, and swirl rather than shake.

Every order includes Free Express Delivery Australia-wide and dispatches within 2 business days of confirmed payment. Keep unmixed vials cool and dark, and refrigerate any reconstituted solution.