Side-by-side comparison
| Property | Cagrilintide | Semaglutide |
|---|---|---|
| Class | Long-acting amylin analogue (amylin/calcitonin receptor agonist) | GLP-1 receptor agonist |
| Hormone mimicked | Amylin (satiety) | GLP-1 (incretin) |
| Brand names | None standalone — part of CagriSema | Ozempic, Wegovy, Rybelsus |
| Approval status (Jun 2026) | Investigational; CagriSema NDA under review | FDA-approved |
| Approximate half-life | ~7 days | ~7 days (SC) |
| Dosing | Once weekly (subcutaneous) | Once weekly SC · once daily oral |
| Time to steady state | ~4–5 weeks | ~4–5 weeks |
| Weight loss (matched trials) | ~11.5% alone; ~22.7% as CagriSema (REDEFINE 1) | ~14.9% alone (2.4 mg) |
See the source-level profiles for cagrilintide and semaglutide, or plot both estimated decay curves with the free half-life calculator.
Mechanism: two appetite hormones, not one
The reason this comparison is so often misunderstood is that both compounds suppress appetite — but through entirely separate hormone systems.
Semaglutide — the GLP-1 lever
Semaglutide mimics GLP-1, an incretin hormone. It stimulates glucose-dependent insulin secretion, suppresses glucagon, slows gastric emptying, and reduces appetite through hypothalamic GLP-1 receptors. It shares 94% sequence homology with native GLP-1.
Cagrilintide — the amylin lever
Cagrilintide mimics amylin, a hormone co-secreted with insulin from pancreatic beta cells after eating. It acts on amylin and calcitonin receptors in the brainstem to enhance satiety, slow gastric emptying, and blunt post-meal glucose spikes. Amylin signaling is non-overlapping with GLP-1, which is the entire scientific premise for combining them.
Why the half-lives matter here
Unlike most "versus" peptide pairs, cagrilintide and semaglutide have nearly the same half-life — roughly 7 days each (cagrilintide ~7.3 days; semaglutide ~6.6 days). Phase 1 work confirmed that cagrilintide does not alter semaglutide's exposure or elimination, and vice versa.
Weight loss: alone vs combined
The numbers tell a consistent story — each works, and together they work better:
- Semaglutide 2.4 mg alone: ~14.9% mean weight loss in matched data.
- Cagrilintide 2.4 mg alone: ~11.5% mean weight loss.
- CagriSema (2.4 mg / 2.4 mg): ~22.7% at 68 weeks in the REDEFINE 1 Phase 3 trial.
Hitting two appetite pathways simultaneously yields more weight loss than maximizing either one alone — the additive effect that justified the combination. For people with type 2 diabetes (REDEFINE 2), CagriSema produced a statistically superior result versus placebo, with meaningful HbA1c improvement. For the broader GLP-1 landscape, compare semaglutide vs tirzepatide and retatrutide vs tirzepatide.
Approval and availability
This shapes any practical decision: semaglutide is something a clinician can prescribe today; cagrilintide is something you will, if approved, most likely receive bundled with semaglutide rather than by itself.
Side effects
Both are dominated by gastrointestinal effects — nausea, vomiting, diarrhea, constipation — concentrated during dose escalation. In CagriSema trials, GI adverse events were common (around 80% of participants) but mostly transient and mild-to-moderate, consistent with the class. A dedicated QT study found cagrilintide did not cause clinically relevant QTc prolongation. As with any GLP-1-based therapy, titration exists specifically to limit these effects.
How they fit the bigger picture
Semaglutide is the established single-pathway GLP-1; tirzepatide adds GIP; retatrutide adds glucagon; and CagriSema takes a different route entirely — pairing GLP-1 with amylin instead of stacking incretins. The full half-life reference for all 44 tracked compounds, including tirzepatide, lives in the compound database, and you can model escalation schedules with the GLP-1 dose-escalation calculator.
Frequently asked questions
What is the difference between cagrilintide and semaglutide?
Semaglutide is a GLP-1 receptor agonist; cagrilintide is an amylin analogue. Different hormones, complementary appetite pathways — which is why they're combined rather than substituted.
Is cagrilintide a GLP-1?
No. It is an amylin analogue. It is paired with the GLP-1 agonist semaglutide in CagriSema, but it acts on different receptors.
Which has a longer half-life?
They're essentially the same — about 7 days each — which is part of why they can share one weekly injection.
Is CagriSema more effective than semaglutide?
In REDEFINE 1, CagriSema reached ~22.7% weight loss at 68 weeks, above semaglutide alone. It targets two pathways at once.
Is cagrilintide FDA approved?
No. Semaglutide is approved; cagrilintide is investigational, and the CagriSema combination's FDA application was filed in December 2025.
Primary sources and further reading
Two pathways, one weekly curve. Track it.
Halflife plots estimated concentration curves for cagrilintide, semaglutide, and 42 other compounds — overlay the near-identical decay lines, model steady state, and log injections in one free iOS app.
Download Halflife →