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 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 real-time 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.
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