Cagrilintide half-life is about 6 to 8 days, which is why it's dosed once weekly. Learn what drives that duration and how it compares with other peptides.
Cagrilintide has a half-life of roughly 6 to 8 days in humans, which is why it is dosed as a once-weekly injection instead of a daily one. That long duration comes from a fatty-acid side chain that lets the peptide bind to albumin in the bloodstream and resist rapid enzyme breakdown. Cagrilintide is an investigational amylin analog, and it is not FDA-approved for human use as a standalone medicine.
What Is Cagrilintide?
Cagrilintide is a synthetic, long-acting analog of human amylin, a hormone the pancreas releases alongside insulin. Like amylin, it slows stomach emptying and promotes a feeling of fullness, which is why researchers study it for weight management.
Novo Nordisk developed cagrilintide and is testing it mainly in combination with semaglutide under the name CagriSema. That combination has been evaluated in the phase 3 REDEFINE clinical program.
- Class: amylin analog
- Route: subcutaneous injection
- Doses studied: once weekly, up to 2.4 mg in trials
- Status: investigational, not approved by any regulator
Cagrilintide Half-Life: What the Numbers Show
Reported half-life values cluster around 150 to 190 hours, or about 6 to 8 days. The exact figure varies with dose, body weight, and how long a person has been taking the drug.
Pharmacokinetic studies in people with obesity and type 2 diabetes show a slow absorption phase after injection, peak blood levels roughly one to three days later, and then a long, flat decline.
A half-life of 6 to 8 days means that after a single dose, about half the drug is cleared within a week. Roughly five half-lives, or 30 to 40 days, are needed before the drug is essentially gone from the body.
Time to steady state
With weekly dosing, blood levels build up over the first month. Most compounds reach steady state after about four to five half-lives, so cagrilintide takes roughly four to five weeks of consistent weekly injections to plateau.
What happens if a dose is missed
Because the half-life is long, a missed dose does not empty the body of drug overnight. Even so, missed doses should be managed with a prescriber, not by doubling up the next injection.
Why Cagrilintide Lasts So Long
Native amylin is short-lived. Pramlintide, the approved amylin analog, has a half-life of about 45 to 50 minutes and must be injected with meals. Cagrilintide was engineered to last far longer.
- Albumin binding: a C20 fatty diacid side chain anchors the peptide to albumin, a protein that circulates for weeks.
- Enzyme resistance: structural changes reduce cleavage by DPP-4 and other peptidases.
- Slow absorption: the molecule leaves the injection site gradually, which flattens the concentration curve.
How the Half-Life Shapes Dosing
Half-life is the main reason cagrilintide is studied as a weekly product. A once-weekly schedule is easier to follow, and steady drug levels avoid the sharp peaks that tend to drive side effects.
A long half-life also means side effects can linger. Nausea and vomiting are the most commonly reported adverse events in trials, and when they occur they may take days or weeks to fade after the drug is stopped.
How Cagrilintide Compares With Other Peptides
Looking at tirzepatide half-life, semaglutide, and cagrilintide side by side shows how much variability exists even among once-weekly drugs.
| Compound | Typical half-life | Usual dosing interval |
|---|---|---|
| Cagrilintide | ~6–8 days | Once weekly |
| Semaglutide | ~1 week | Once weekly |
| Tirzepatide | ~5 days | Once weekly |
| Liraglutide | ~13 hours | Once daily |
| Pramlintide | ~48 minutes | With each meal |
Not every peptide behaves this way. Somatropin half-life is measured in hours rather than days, and melanotan ii half life and pt-141-half-life are also far shorter. Even among sleep- and recovery-related compounds, dsip half life and similar figures can differ by orders of magnitude.
Safety and Legal Status
Cagrilintide is not approved by the FDA or any other regulator for human use. Any product sold online as "cagrilintide" is unregulated, and its identity, purity, and sterility cannot be assumed.
Side effects reported in trials include nausea, vomiting, diarrhea, constipation, and injection-site reactions. These are common across amylin- and GLP-1-based therapies and are usually strongest during dose escalation.
Anyone considering cagrilintide or CagriSema should talk with a licensed healthcare professional. Self-dosing with research-grade peptides carries real risks, including contamination, dosing errors, and untreated side effects.
Half-life tells you how long a drug stays in the body. It does not tell you whether that drug is safe or appropriate for you, and that question belongs with a clinician who knows your history.
Frequently Asked Questions
How long does cagrilintide stay in your system?
Cagrilintide has a half-life of about 6 to 8 days, so it takes roughly 30 to 40 days, or about five half-lives, for the drug to be essentially cleared after the last dose. With weekly dosing, blood levels also take about four to five weeks to reach steady state. Individual timing varies with dose, body weight, and kidney and liver function.
Is cagrilintide FDA-approved?
No. Cagrilintide is an investigational amylin analog and is not approved for human use by the FDA or any other regulator. It is being studied mainly in combination with semaglutide under the name CagriSema. Products sold online as cagrilintide are unregulated and their purity and sterility are not guaranteed.
Does a long half-life make cagrilintide safer?
No. A longer half-life mainly changes how often the drug is injected and how smoothly levels stay in the body. It does not reduce the risk of side effects, and it can actually prolong them, since nausea or vomiting may persist for days after a dose is stopped. Anyone using cagrilintide should do so only under medical supervision in a clinical trial setting.
This page provides educational research information and does not replace medical advice, diagnosis, or treatment.