CagriSema (revision 8)

CagriSema is an investigational fixed-ratio combination of the amylin analogue cagrilintide and the GLP-1 receptor agonist semaglutide, co-formulated for weekly subcutaneous administration in a single injection. It is not approved for use in any indication.^[1]

It differs architecturally from the unimolecular dual agonists: rather than one peptide engaging two receptors, CagriSema is two peptides in one syringe. The ratio is therefore set at formulation rather than by chemistry, and the two components retain their own pharmacokinetics — an advantage for design flexibility and a complication for exposure matching.^[2]

The rationale is mechanistic complementarity. Amylin and GLP-1 promote satiety through partly separate hindbrain circuits, and the combination has produced greater weight reduction than either component alone in the trials reported to date.^[1]

Amylin acts principally at the area postrema through calcitonin-receptor complexes; GLP-1 acts at the area postrema and at hypothalamic arcuate circuits through the GLP-1 receptor. The pathways converge on food intake but are pharmacologically separable, and preclinical work indicated additivity rather than redundancy.^[2]

Both components also slow gastric emptying, which is where the mechanisms overlap most and where the tolerability cost of combining them is expected to concentrate.

The co-formulation approach was chosen over a unimolecular design because no scaffold engages both the GLP-1 receptor and an amylin receptor — the receptor families are not related in the way the incretin and glucagon receptors are, so the trick that produced tirzepatide is not available here.^[1]