Cagrilintide is a long-acting version of amylin, a hormone the pancreas releases alongside insulin. It is being developed mainly as a partner to semaglutide in the combination called CagriSema, which is why most side-effect figures that circulate under its name are really figures for two drugs at once.
This page reports the record for cagrilintide on its own: one completed trial with posted results, read arm by arm. The dose arms themselves are set out on our cagrilintide dosage page; Peptide Lexicon's cagrilintide entry and its amylin entry explain the molecule and the hormone it copies; the combination is GLP1Ledger's subject on its CagriSema page. Nothing here is a recommendation, and cagrilintide has no approved use.
The trial the numbers come from
NCT03856047 is a phase 2, double-blind, dose-finding trial at 57 sites in ten countries, published by Lau and colleagues in The Lancet in December 2021. Adults with obesity, or overweight with high blood pressure or high cholesterol, and without diabetes, injected cagrilintide once a week at one of five doses — 0.3, 0.6, 1.2, 2.4 or 4.5 mg — or a matched placebo, with liraglutide 3.0 mg daily as an active comparator. Treatment ran 26 weeks, including up to 6 weeks of dose escalation, then 6 weeks without treatment. Novo Nordisk sponsored it.
The paper's abstract gives the headline: gastrointestinal adverse events in 41–63% of the cagrilintide arms against 32% on placebo, mainly nausea (20–47% against 18%). Permanent discontinuation (10% overall) was similar across groups, mostly because of adverse events (4%).
The posted table, arm by arm
The registry record carries the full adverse-event table for weeks 0 to 32, posted by the sponsor. Rows are events reported in at least 5% of any arm (the record's stated threshold); percentages are our arithmetic from the posted counts.
| Event | Placebo (n=101) | 0.3 mg (101) | 0.6 mg (100) | 1.2 mg (102) | 2.4 mg (102) | 4.5 mg (101) | Liraglutide 3.0 mg (99) |
|---|---|---|---|---|---|---|---|
| Nausea | 18 (18%) | 20 (20%) | 27 (27%) | 37 (36%) | 32 (31%) | 47 (47%) | 39 (39%) |
| Constipation | 7 (7%) | 11 (11%) | 9 (9%) | 8 (8%) | 17 (17%) | 21 (21%) | 26 (26%) |
| Diarrhoea | 9 (9%) | 15 (15%) | 10 (10%) | 8 (8%) | 18 (18%) | 7 (7%) | 18 (18%) |
| Vomiting | 3 (3%) | 6 (6%) | 6 (6%) | 5 (5%) | 9 (9%) | 8 (8%) | 20 (20%) |
| Decreased appetite | 4 (4%) | 4 (4%) | 9 (9%) | 8 (8%) | 13 (13%) | 17 (17%) | 9 (9%) |
| Fatigue | 3 (3%) | 8 (8%) | 5 (5%) | 8 (8%) | 10 (10%) | 20 (20%) | 8 (8%) |
| Dizziness | 3 (3%) | 8 (8%) | 2 (2%) | 8 (8%) | 9 (9%) | 9 (9%) | 5 (5%) |
| Headache | 12 (12%) | 10 (10%) | 5 (5%) | 11 (11%) | 11 (11%) | 7 (7%) | 13 (13%) |
| Injection-site redness | 0 | 5 (5%) | 4 (4%) | 6 (6%) | 7 (7%) | 17 (17%) | 3 (3%) |
| Injection-site reaction | 0 | 4 (4%) | 4 (4%) | 7 (7%) | 12 (12%) | 10 (10%) | 1 (1%) |
| Injection-site itching | 0 | 5 (5%) | 2 (2%) | 4 (4%) | 7 (7%) | 7 (7%) | 3 (3%) |
ClinicalTrials.gov results for NCT03856047, safety analysis set, read 28 October 2026.
Three patterns are visible in the counts. Nausea climbs with dose but not in a straight line — the 1.2 mg arm sits above the 2.4 mg arm, which is the noise one expects at about a hundred people per group. Vomiting stays low on cagrilintide at every dose, between 5 and 9%, against 20% on liraglutide. And injection-site reactions are cagrilintide's own: zero on placebo, single digits at the lower doses, and up to 17% redness at 4.5 mg. Fatigue at the top dose (20% against 3% on placebo) is the other figure that stands out.
Serious events
Serious adverse events by arm: placebo 3 of 101, 0.3 mg 6 of 101, 0.6 mg 2 of 100, 1.2 mg 7 of 102, 2.4 mg 3 of 102, 4.5 mg 4 of 101, liraglutide 4 of 99. No deaths were recorded in any arm. The posted list is a scatter of single cases — pulmonary embolism (one each at 1.2 and 2.4 mg), deep vein thrombosis (one each at 1.2 and 2.4 mg), gallstones (one at 4.5 mg, one on liraglutide), biliary colic (one at 1.2 mg), a stroke (1.2 mg), delirium (4.5 mg), and others unrelated to any organ system in particular. At these numbers, no single serious event can be separated from chance, and the trial was not designed to do so. Pancreatitis does not appear in the serious-event list.
Why CagriSema figures are not cagrilintide figures
The phase 3 programme, REDEFINE, tests the combination. REDEFINE 1 (Garvey et al., NEJM, August 2025; NCT05567796) randomised 3,417 adults 21:3:3:7 to CagriSema, semaglutide 2.4 mg alone, cagrilintide 2.4 mg alone (302 people) or placebo for 68 weeks. Its abstract reports gastrointestinal adverse events of 79.6% on the combination and 39.9% on placebo — and gives no figure for the cagrilintide-alone arm. The registry record was "active, not recruiting" with no posted results when we read it on 28 October 2026, so the 68-week monotherapy table is not public in the registry. Until it is, the 26-week phase 2 table above is the only arm-by-arm safety record for cagrilintide by itself.
A second phase 3 study with a cagrilintide-only arm, NCT07253285, is in children and adolescents and was recruiting with no results, as recorded on our dosage page.
What is not established
- Side effects beyond 32 weeks for cagrilintide alone: no longer monotherapy results are posted.
- Rare events — pancreatitis, gallbladder disease, thyroid findings, heart-rate changes — at rates that could be compared with the GLP-1 drugs. A trial of about a hundred per arm cannot measure them.
- Anything from anyone but the developer. Every registered cagrilintide trial is sponsored by Novo Nordisk; there is no independent safety record.
- Products sold online as research cagrilintide, which come with no label, no trial and no quality record. Our page on how to read a certificate of analysis explains what a seller's document can and cannot show.
The class-wide picture of nausea, constipation and injection-site reactions across peptide drugs is on our peptide side effects page, and local reactions in particular on peptide injection-site reactions. Anyone weighing an investigational drug should do so with a clinician, inside a trial or under a prescription.
Sources and dates
- ClinicalTrials.gov, NCT03856047 — posted results, adverse events module (weeks 0–32, safety analysis set), read via API v2 on 28 October 2026.
- Lau DCW et al. Once-weekly cagrilintide for weight management in people with overweight and obesity. Lancet 2021;398:2160–72. doi:10.1016/S0140-6736(21)01751-7 (PubMed 34798060 abstract, read 28 October 2026).
- Garvey WT et al. Coadministered cagrilintide and semaglutide in adults with overweight or obesity (REDEFINE 1). N Engl J Med 2025;393:635–647. doi:10.1056/NEJMoa2502081 (PubMed 40544433 abstract, read 28 October 2026).
- ClinicalTrials.gov, NCT05567796 (REDEFINE 1) record: status and results availability, read 28 October 2026.