CagriSema (cagrilintide + semaglutide)

Mechanism of action

CagriSema pairs two mechanistically distinct appetite-suppressing peptides in a single weekly injection: cagrilintide (a long-acting amylin analogue engaging the calcitonin-receptor family and specifically the amylin receptor complex CTR + RAMP) and semaglutide (the licensed GLP-1 receptor agonist). The pharmacological rationale is complementary rather than redundant — amylin and GLP-1 act through distinct receptor systems in overlapping but non-identical central nervous system circuits regulating appetite and satiety. Cagrilintide's amylin-mimetic mechanism engages hypothalamic and brainstem calcitonin-family receptors, driving satiety through pathways separate from GLP-1R engagement. Native amylin is co-secreted with insulin from pancreatic β-cells; its physiological role in postprandial satiety complements GLP-1's incretin-effect insulin secretion. Combining pharmacological amylin and GLP-1 receptor engagement produces additive rather than merely additive appetite suppression — mechanistic non-overlap allows both pathways to contribute independently to reduced caloric intake. Semaglutide's GLP-1R agonism has been discussed extensively elsewhere on this reference: glucose-dependent insulin secretion, glucagon suppression, delayed gastric emptying, central appetite reduction through hypothalamic and brainstem GLP-1R populations. In CagriSema, semaglutide provides the incretin arm; cagrilintide provides the amylin-receptor arm. Clinical data from the Phase II programme demonstrated additive weight-loss effects: cagrilintide 2.4 mg + semaglutide 2.4 mg produced ~15.6% weight loss over 32 weeks in adults with obesity, compared with ~5.1% for cagrilintide alone and ~5.1% for semaglutide alone at matched doses in the same trial. The Phase II data supports the combination-therapy rationale and motivated the Phase III REDEFINE programme. The cagrilintide component is not independently licensed as a standalone medicine — Novo Nordisk pursued CagriSema development directly rather than dual-licensing pathways. Cagrilintide's structural design shares the amylin-mimetic architecture pioneered by pramlintide (the older short-acting amylin analogue historically used adjunctively with insulin) but with fatty-acid acylation for the extended half-life required for weekly rather than mealtime dosing.

CagriSema's Phase II data demonstrated ~3x greater weight loss for the combination versus either monotherapy at matched doses — clean empirical support for the amylin + GLP-1 combination-therapy hypothesis. If Phase III REDEFINE confirms this magnitude and safety, CagriSema will be Novo Nordisk's principal next-generation weight-loss pharmacology competing with tirzepatide and retatrutide.

— Notable finding

Research history

CagriSema emerged from Novo Nordisk's incretin-and-adjacent-pathway research portfolio in the mid-to-late 2010s as the company sought next-generation weight-loss compounds extending beyond semaglutide monotherapy. Cagrilintide was designed as a long-acting amylin analogue building on Novo Nordisk's earlier pramlintide-related pharmacology (though pramlintide itself was developed by Amylin Pharmaceuticals, later acquired by Bristol-Myers Squibb, and licensed as Symlin for mealtime insulin adjunct use in diabetes). The combination-therapy hypothesis — that amylin and GLP-1 agonism would produce additive weight loss through complementary appetite-regulatory mechanisms — was tested through Phase I and Phase II development across 2019-2022. Phase II data reported in 2022 demonstrated the anticipated additive effect (Enebo et al., Lancet 2021, Frías et al. Lancet 2023) motivating advancement to Phase III. The Phase III REDEFINE programme initiated in 2023 encompasses REDEFINE-1 (obesity), REDEFINE-2 (obesity with type-2 diabetes), REDEFINE-3 (cardiovascular outcomes), REDEFINE-4 (obesity and osteoarthritis), and additional trials. Primary readouts are expected across 2025-2027, with regulatory filings anticipated 2026-2028 dependent on trial progress. As of 2026, CagriSema is not licensed in any jurisdiction. Access is restricted to Phase III clinical-trial participation. The programme represents Novo Nordisk's principal near-term extension of the semaglutide franchise into next-generation weight-loss pharmacology, competing directly with Eli Lilly's tirzepatide (dual GLP-1R/GIPR agonism, already licensed) and retatrutide (triple GLP-1R/GIPR/glucagon-R agonism, in Phase III).

Reported research-model dose ranges

The ranges below are taken from published pre-clinical literature. They do not constitute a dosing recommendation for human use.

Summarised studies

Safety profile

CagriSema's safety profile combines the class characteristics of GLP-1R agonism (gastrointestinal predominance) with the additional characteristics of amylin-receptor agonism. Phase II data showed the gastrointestinal adverse-event profile (nausea, vomiting) was broadly similar to semaglutide monotherapy at matched semaglutide dose, without meaningful worsening from the added cagrilintide component. This suggests that combination therapy does not multiply GI adverse events even though both components engage the appetite-suppressing pathway. Cagrilintide-specific adverse events include injection-site reactions (potentially slightly higher than semaglutide alone given the added component) and rare hypoglycaemia in insulin-treated diabetes contexts (amylin's insulin-adjacent pharmacology affects postprandial glucose profiles). Cardiovascular safety expectations parallel the semaglutide component's favourable cardiovascular profile as established in SELECT and related trials. The REDEFINE-3 cardiovascular-outcome trial will provide the definitive cardiovascular safety and benefit data for the combination. Theoretical concerns about additive central nervous system effects from combined amylin and GLP-1 receptor engagement have not surfaced clinically at Phase II magnitudes. The full Phase III programme will provide the larger and longer-duration safety dataset required for regulatory review. The FDA-mandated thyroid C-cell carcinoma class warning applies via the semaglutide component. Longer-term rare adverse events (acute pancreatitis, biliary disease, retinopathy) will be characterised through REDEFINE Phase III and eventual post-marketing surveillance.

UK regulatory status

CagriSema is **not** authorised as a medicinal product by the UK Medicines and Healthcare products Regulatory Agency (MHRA) and holds **no marketing authorisation** in any jurisdiction as of 2026. The combination is in Phase III clinical development by Novo Nordisk through the REDEFINE programme; first regulatory filings are anticipated 2026-2028. Access is restricted to Phase III clinical-trial participation at selected UK NHS and private clinical-trial sites. Supply outside the clinical-trial framework is not legally available through MHRA-regulated channels. Both component peptides (cagrilintide and semaglutide) have some grey-market and research-chemical-market presence, particularly semaglutide given its licensed status and market prominence. Combined-product supply outside authorised channels is generally not the pattern — the components are more commonly seen individually. Supply for human use engages the Human Medicines Regulations 2012. CagriSema is not on the WADA Prohibited List (the GLP-1R class and amylin-family compounds are not currently prohibited). Not a controlled drug under the Misuse of Drugs Act 1971. For animal research under ASPA, both component peptides require standard project and personal licences.

Frequently asked questions