What is cagrilintide? What it does, benefits and what the evidence shows

Cagrilintide is a long-acting amylin analogue developed by Novo Nordisk, the same company behind semaglutide (Ozempic, Wegovy). It's not approved by the FDA on its own, and its biggest headline is really someone else's compound's headline too: paired with semaglutide in a fixed-dose combination called CagriSema, it produced some of the largest weight-loss numbers yet reported in a Novo Nordisk obesity trial. Cagrilintide alone has also been tested in a large phase 3 trial. Cagrilintide on its own isn't an approved drug; Novo Nordisk submitted CagriSema to the FDA for approval in December 2025. This isn't medical advice.

What cagrilintide is and how it works

Amylin is a hormone the body releases alongside insulin, and Novo Nordisk describes cagrilintide as a long-acting amylin analogue — a lab-made molecule engineered to mimic that hormone's action but last far longer in the body than natural amylin (Novo Nordisk's own description, in its December 2025 announcement that it had submitted CagriSema for FDA approval, describes cagrilintide as "a long-acting amylin analogue" and CagriSema as a combination of GLP-1 and amylin analogues for weight management (Novo Nordisk, PR Newswire, December 18, 2025)). Novo Nordisk's own summary of the REIMAGINE 2 type 2 diabetes trial calls the CagriSema components "a long-acting amylin receptor agonist, cagrilintide, and a long-acting GLP-1 receptor agonist, semaglutide" working through separate receptor systems (Novo Nordisk company announcement). Novo Nordisk's CEO has framed the pairing as combining "the well-established profile of semaglutide" with "a novel mechanism of action" in cagrilintide, rather than simply doubling up on the GLP-1 pathway (same PR Newswire release).

There's no approved brand name for cagrilintide by itself. The combination product is CagriSema (cagrilintide 2.4 mg / semaglutide 2.4 mg), and the logic behind pairing the two is that amylin and GLP-1 act through separate receptor systems, so combining them is a different bet than simply raising the dose of one drug. Grey-market listings, sometimes shortened to "cagri" in buyer forums, sell cagrilintide as a standalone research chemical, "for research use only," separate from and unaffiliated with Novo Nordisk's clinical program.

What people use it for

Cagrilintide has not been studied or approved for anything outside weight management and glycemic control in these trials. Claims about muscle sparing, anti-aging or general "biohacking" benefits circulate in grey-market marketing, but we found no human trial data behind them, so they're graded anecdotal and left out of the discussion below.

What the research actually shows

REDEFINE 1: cagrilintide alone versus the combination

REDEFINE 1 was Novo Nordisk's pivotal phase 3 trial in 3,417 adults with obesity or overweight and at least one weight-related condition, without type 2 diabetes, randomized to CagriSema, semaglutide alone, cagrilintide alone, or placebo over 68 weeks. Novo Nordisk's own topline results, reported through HCPLive, put mean weight loss at 22.7% for CagriSema, 16.1% for semaglutide alone, 11.8% for cagrilintide alone, and 2.3% for placebo, with a mean baseline body weight of 106.9 kg across the trial (HCPLive, reporting Novo Nordisk's announcement). Those figures reflect people who stayed on treatment; by week 68, 82.5% of the cagrilintide-alone group had reached the highest dose, versus 57.3% of the CagriSema group, an indication that the combination was harder for some people to tolerate up to the top dose (same source).

The trial's headline result, published in the New England Journal of Medicine, is usually quoted a different way: the "treatment policy" estimand, which counts everyone regardless of whether they stayed on treatment, showed CagriSema produced 20.4% average weight loss versus 3.0% for placebo, a difference Novo Nordisk's release called statistically significant, alongside secondary findings that 34.7% of participants on CagriSema reached at least 25% weight loss and 19.3% reached at least 30% (PR Newswire / Novo Nordisk). Both sets of numbers are real; they answer slightly different questions (what happens if you stay on it, versus what happens to everyone who starts it), and it's worth knowing which one a source is quoting before comparing it to another drug's trial.

REDEFINE 1 is the only large cagrilintide-alone result we found published so far. ClinicalTrials.gov also lists standalone cagrilintide Phase 3 trials that started in November 2025, including NCT07220642 in adults with overweight or obesity and NCT07220759 in adults with obesity and type 2 diabetes, so the drug is no longer only a CagriSema component; we found no results from them yet (ClinicalTrials.gov NCT07220642).

REDEFINE 2 and REIMAGINE 2: cagrilintide in type 2 diabetes

REDEFINE 2 tested CagriSema in 1,206 adults with type 2 diabetes over 68 weeks; per a secondary report of the trial, CagriSema produced 13.7% mean weight loss versus 3.4% for placebo, with 74% of participants reaching a hemoglobin A1c of 6.5% or below, versus 15.9% on placebo (American College of Cardiology journal scan of REDEFINE 1 and REDEFINE 2). A separate, later trial, REIMAGINE 2, again in type 2 diabetes, compared CagriSema against semaglutide alone, cagrilintide alone and placebo over 68 weeks in 2,728 participants; Novo Nordisk's own announcement reported CagriSema produced a 1.91-percentage-point drop in HbA1c and 14.2% weight loss, against 1.76 points and 10.2% for semaglutide alone, with 43% of participants reaching at least 15% weight loss and 24% reaching at least 20% (Novo Nordisk company announcement). Neither release gave a separate weight-loss figure for cagrilintide alone in REIMAGINE 2's diabetes population, so we can't state one.

Safety in the trials

Across REDEFINE 1, gastrointestinal side effects — mainly nausea, constipation and vomiting — were reported in 79.6% of the CagriSema group versus 39.9% on placebo; Novo Nordisk characterized them as mostly mild-to-moderate and transient, and discontinuation due to adverse events ran 6% on CagriSema versus 3.7% on placebo (PR Newswire / Novo Nordisk). That safety picture describes CagriSema, the combination, and it's not the same thing as safety data on cagrilintide taken alone long-term, or on a research-labeled cagrilintide vial with no clinical oversight.

Where it stands with the FDA

We found no FDA filing for cagrilintide by itself; the product Novo Nordisk has filed is the CagriSema combination, although the company is also running standalone cagrilintide Phase 3 trials. Novo Nordisk submitted a new drug application for CagriSema to the FDA on December 18, 2025, for weight management, based on the REDEFINE trials in roughly 4,600 adults; the company's December 2025 release states plainly, "CagriSema is not approved in the US or EU," and says the FDA is expected to review it during 2026 (Novo Nordisk, PR Newswire, December 18, 2025); a February 2026 trade report cited a decision anticipated by late 2026. In February 2026 Novo Nordisk also reported that in the 809-person, 84-week REDEFINE 4 trial CagriSema did not meet its non-inferiority goal against tirzepatide (23.0% versus 25.5% weight loss, primary estimand) (Clinical Trials Arena, February 2026). Novo Nordisk has separately said it will discuss a regulatory pathway for the type 2 diabetes indication with authorities (Novo Nordisk company announcement). Nothing sold today as cagrilintide, standalone or in a grey-market blend marketed as a CagriSema equivalent, is an FDA-approved product, regardless of what the trial data eventually shows about the real drug.

Side effects and risks

In Novo Nordisk's own trials, cagrilintide's side-effect profile — reported as part of CagriSema — was dominated by gastrointestinal symptoms typical of the GLP-1/amylin drug class: nausea, constipation, vomiting, mostly mild to moderate and easing over time, alongside a modestly higher discontinuation rate than placebo. That's the extent of the human safety data we could verify, and it comes from a supervised clinical trial with medical monitoring, dose titration and a defined population — not from taking a research-labeled vial off a grey-market listing.

What's genuinely unknown: cagrilintide has no FDA-reviewed long-term safety record on its own, no approved manufacturing standard, and no post-marketing surveillance, because it isn't an approved drug. Every safety figure above comes from a trial population that was screened, monitored and dose-titrated by clinicians over a fixed 68-week window; nobody has published what happens with unsupervised, indefinite use, at whatever amount a vial actually contains, and that gap doesn't close just because the CagriSema trials look reassuring. A grey-market vial sold as "cagrilintide" carries the added, separate risk that it may not contain what the label says, at the purity or amount claimed — a manufacturing and vendor-integrity risk, distinct from anything the clinical trials measured.

What the lab tests show

As of September 30, 2026, VendorVerify's database includes 12 cagrilintide vials from 5 vendors, drawn from 8 lab reports dated November 2024 through August 2026 — a sample where a single vendor's results can move the numbers noticeably. 12 of the 12 tested vials have a purity result, and 11 of those came in at 99% or higher, with median purity 99.60%. On dose versus label, the median measured amount ran 11.1% over label; 5 of the 12 vials landed within ±5% of label and 2 measured more than 20% over. As of September 29, 2026, none of the 12 vials had failed by our definition (empty, under 95% pure, more than 20% under label, or more than 50% over).

That's a clean-looking small sample, but it's genuinely thin — 5 vendors and 8 reports (as of September 29, 2026) is not enough to draw firm conclusions about the compound as a whole, and it says nothing about whether a given vial actually contains cagrilintide at all, since standard purity and quantity testing measures the peptide against its expected mass and chromatographic profile, not against an independent identity confirmation in every case. No endotoxin, sterility, TFA or heavy-metal results have been submitted for cagrilintide in our data yet, which is worth knowing if you've seen those figures quoted for other compounds and assumed they exist here too — for cagrilintide, right now, they simply haven't been tested and reported to us.

Here's how the ranked vendors look right now for this compound. The table below shows current verdicts and flags any vendor with more than 5% failed vials; being ranked isn't automatically good, and with this little data, the table may be short.

Buying smarter

Check the vendor's specific record for cagrilintide at /peptides/cagrilintide rather than their reputation generally — a vendor can be solid on tirzepatide and thin on a newer compound like this one. Look at whether a posted certificate of analysis is a vendor-supplied document or an independently commissioned lab report, and verify it rather than trusting it on sight; /blog/how-to-read-a-peptide-coa and our guide to fake certificates cover what to check. If you want your own answer rather than someone else's, how to get a peptide tested walks through ordering identity, purity and quantity testing from an independent lab. If a report on your vial comes back bad, stop using that batch, tell anyone else who bought from the same run, bring the report to the vendor, and submit it to VendorVerify so it's part of the public record. General background on this market is at what are gray market peptides, and the closely related compound in most of the trial data above is covered in what is semaglutide.

Trial and regulatory figures above are from Novo Nordisk's own announcements and press materials, cited individually. Database figures without a date update automatically from VendorVerify's lab results; dated figures are snapshots. This isn't medical advice.