CagriSema

CagriSema is the development name of an investigational once-weekly subcutaneous injection that puts two different peptide hormones analogues into a single co-formulated product: cagrilintide, a long-acting analogue of human amylin, and semaglutide, the GLP-1 receptor agonist already marketed under other brand names for type 2 diabetes and for weight management. The phase 3 program studied the combination at cagrilintide 2.4 mg with semaglutide 2.4 mg, which is why the product is often written as CagriSema 2.4/2.4.

The two molecules are chemically distinct. Cagrilintide is a 32-amino-acid peptide built on an amylin backbone, stabilized against the aggregation that makes native human amylin difficult to use as a drug, and acylated with a C18 fatty diacid side chain that extends its half-life to a once-weekly interval. Semaglutide is a 31-amino-acid GLP-1 analogue with an aminoisobutyric acid substitution that blocks degradation by DPP-4 and a fatty acid side chain that binds albumin. They are not fused into one molecule: CagriSema is a fixed-dose pairing of two separate peptides delivered together.

That distinction matters when reading the literature. The single-agent story of the amylin analogue is covered in our cagrilintide guide, and the GLP-1 story in our semaglutide guide. This page is about the combination itself: what adding amylin signaling to GLP-1 signaling actually bought in phase 3, and what it did not.

A fixed-dose format also constrains how the product can be used. Because both components escalate together, a person who tolerates the GLP-1 component well but reacts poorly to the amylin component (or the reverse) cannot have one adjusted independently. That design choice is part of why the trial results have been debated as much as celebrated.

Disclaimer: CagriSema is an investigational product. It is not approved for human use in the United States or the European Union, and this article is for educational purposes only. Consult a qualified healthcare professional for any individual medical question.

Amylin and GLP-1 are two separate satiety signals with two separate receptor systems. Amylin is a 37-amino-acid hormone co-secreted with insulin by pancreatic beta cells after a meal. It slows gastric emptying, suppresses glucagon secretion, and acts on the area postrema and the hindbrain to promote meal termination and satiation. GLP-1 is an incretin released by intestinal L cells that enhances glucose-dependent insulin secretion and reduces appetite largely through hypothalamic and brainstem GLP-1 receptors.

Because the two hormones converge on energy intake through partly non-overlapping circuits, the pharmacological bet was that stimulating both would produce more weight loss than saturating either pathway alone. Preclinical work supports a distinct central mechanism for the amylin component: a 2025 eBioMedicine study showed that cagrilintide requires brain amylin receptors AMY1R and AMY3R to lower body weight in rodent models, confirming that it is not simply working through the same receptors as incretin drugs.

The clinical groundwork came first from a phase 1b trial published in The Lancet in 2021, which tested escalating cagrilintide alongside semaglutide 2.4 mg and found the co-administration tolerable with greater weight reduction than semaglutide alone over the short exposure. A separate phase 2 dose-finding trial of cagrilintide as monotherapy, also published in The Lancet in 2021, established that an amylin analogue on its own produces clinically meaningful weight loss, which made the combination worth taking into phase 3.

This logic of stacking complementary gut and pancreatic hormone pathways is the same thread running through the wider field of next-generation incretin therapies, where developers are combining GLP-1 with GIP, glucagon, or amylin signaling rather than simply pushing GLP-1 doses higher. CagriSema is the amylin branch of that strategy and, so far, the most advanced one.

The important nuance is that complementary does not automatically mean additive. Part of what REDEFINE 1 was designed to answer was precisely how much the amylin component adds once GLP-1 signaling is already maximized.

REDEFINE 1 is the pivotal obesity trial, published in the New England Journal of Medicine in 2025 by Garvey and colleagues. It was a 68-week, double-blind, phase 3a trial in 3,417 adults without diabetes who had a body mass index of 30 kg/m² or above, or 27 kg/m² or above with at least one weight-related complication. Participants were randomized in a 21:3:3:7 ratio to cagrilintide-semaglutide (n=2,108), semaglutide 2.4 mg alone (n=302), cagrilintide 2.4 mg alone (n=302), or placebo (n=705), all with lifestyle intervention.

Under the treatment policy analysis, which counts everyone as randomized regardless of whether they stayed on treatment, the estimated mean change in body weight from baseline to week 68 was -20.4% with the combination versus -3.0% with placebo, an estimated difference of 17.3 percentage points. The two monotherapy arms landed in between: -14.9% with semaglutide alone and -11.5% with cagrilintide alone.

Under the analysis that estimates the effect if all participants had adhered to treatment, the figures were -22.7% for the combination, -16.1% for semaglutide, -11.8% for cagrilintide and -2.3% for placebo. Both readings tell the same qualitative story: the combination outperformed each of its components, and the amylin analogue contributed a real increment on top of a GLP-1 agonist already given at its highest established weight-management dose.

The gap between the two sets of numbers is not a contradiction but a reminder of how modern trials are reported. The treatment policy estimand is the conservative, real-world-flavored reading; the trial product estimand describes the drug's pharmacological potential under ideal adherence. Any comparison between products should hold the estimand constant, which is a recurring source of confusion in popular coverage of obesity drugs.

Among the practical details disclosed around the readout, the trial used a flexible approach in which participants could step down if tolerability required it, and the sponsor reported that roughly 57% of participants were on the highest combination at the end of the trial. That figure became central to the debate described in the next section.

When Novo Nordisk released the REDEFINE 1 topline on December 20, 2024, the trial had met its primary endpoint with a clear margin over placebo and over both monotherapies. Markets reacted badly anyway. The company had previously guided toward a weight reduction of at least 25%, and the headline figure came in at 22.7%. Novo Nordisk shares fell steeply on the announcement, one of the sharpest single-day moves in the company's recent history.

Two explanations were offered at the time, and both deserve a neutral hearing. The first is the flexible dosing design: because participants could reduce the dose for tolerability, only about 57% were on the highest combination at week 68, which mechanically dilutes the average effect compared with a forced-titration design. The second is simply that the biological ceiling of this particular pairing may sit closer to 23% than to 25% in an unselected population.

It is worth separating three different questions that got blended together in the coverage. Did the drug work? Yes, by a wide margin against placebo. Did amylin add value on top of GLP-1? Yes, roughly 5 to 6 percentage points of additional weight loss versus semaglutide alone in the same trial. Did it beat the commercial expectation the sponsor itself had set? No. Only the third question is about disappointment, and it is a market question rather than a clinical one.

That said, the expectation gap has real downstream consequences. It shaped the competitive framing against tirzepatide, it influenced how the later head-to-head trial was read, and it is why Novo Nordisk has since announced plans for a higher-dose program and an additional trial, REDEFINE 11, designed to probe the full weight-loss potential of the combination, with data expected in the first half of 2027.

For readers evaluating the evidence rather than the share price, the honest summary is that REDEFINE 1 was a positive trial that fell short of a promise the sponsor should probably not have made.

REDEFINE 2, published in the New England Journal of Medicine in 2025 by Davies and colleagues, tested the same combination in a harder population: 1,206 adults from 12 countries with type 2 diabetes, a body mass index of 27 kg/m² or above, and a glycated hemoglobin between 7% and 10%. Participants were randomized 3:1 to cagrilintide-semaglutide or placebo for 68 weeks, with lifestyle intervention in both arms. Mean baseline glycated hemoglobin was 8.0%.

The estimated mean change in body weight from baseline to week 68 was -13.7% with the combination versus -3.4% with placebo under the treatment policy analysis. Under the analysis assuming full adherence, the weight reduction approached 16%. Both figures are lower than the obesity trial, which is the expected and well-documented pattern: people with type 2 diabetes consistently lose less weight on incretin-based therapy than people without diabetes, across every drug class studied so far.

Glycemic results were substantial. At week 68, 73.5% of participants in the combination group had a glycated hemoglobin of 6.5% or less, compared with 15.9% in the placebo group. For a population entering the trial at a mean of 8.0%, that is a large shift in glycemic control achieved alongside double-digit weight reduction.

REDEFINE 2 matters for the regulatory and clinical picture in a specific way: it establishes that the amylin plus GLP-1 pairing retains both metabolic effects in the population where obesity pharmacotherapy is hardest to deliver, and it supports the dual positioning of the product across obesity and diabetes rather than obesity alone.

As always, group averages conceal wide individual variation. Trial populations are selected, supported and monitored in ways that routine care is not, and results observed over 68 weeks say nothing definitive about what happens over five or ten years.

Weight is the headline endpoint, but the metabolic consequences matter more for long-term health. A secondary analysis of REDEFINE 1 published in Hypertension in 2026 by Verma and colleagues examined blood pressure. From baseline to week 68, systolic blood pressure fell by 10.9 mm Hg with the combination versus 2.8 mm Hg with placebo, and diastolic blood pressure by 5.4 mm Hg versus 1.7 mm Hg.

The same analysis reported that 63.0% of participants on the combination reached blood pressure targets at week 68 versus 32.0% on placebo, and that among participants taking antihypertensive medication, 39.6% in the combination group reduced or stopped that medication during the trial versus 18.8% on placebo. Blood pressure reduction of this magnitude is consistent with what is seen across effective weight-loss pharmacotherapy and is largely, though not necessarily entirely, weight mediated.

On the diabetes side, a separate phase 3 program read out in 2026. REIMAGINE 2, published in The Lancet Diabetes and Endocrinology, compared cagrilintide-semaglutide against semaglutide alone, cagrilintide alone and placebo in type 2 diabetes. The mean change in glycated hemoglobin was significantly greater with the combination at 2.4/2.4 mg than with semaglutide 2.4 mg (-1.91 versus -1.75 percentage points, p=0.0035), confirming an incremental glycemic benefit from the amylin component, though a modest one.

What is conspicuously absent from the current evidence base is hard cardiovascular outcome data. REDEFINE 3, an event-driven trial of roughly 7,000 adults with established cardiovascular disease and overweight or obesity, is fully randomized and ongoing, with a readout anticipated in the second half of 2027. Until it reports, claims about cardiovascular event reduction with this specific combination remain extrapolation from surrogate markers and from what is known about the semaglutide component.

The tolerability profile of CagriSema is dominated by gastrointestinal effects, which is unsurprising given that both components independently slow gastric emptying and act on brainstem nausea circuits. In REDEFINE 1, gastrointestinal adverse events were reported in 79.6% of participants receiving the combination versus 39.9% on placebo. Nausea was reported by 55% versus 12.6%, and constipation by 30.7% versus 11.6%.

Most of these events were described as mild to moderate, transient, and concentrated during the escalation phase rather than persisting through the maintenance period. Discontinuation because of adverse events was 6.0% with the combination versus 3.7% with placebo in REDEFINE 1, a low figure in absolute terms and a reminder that frequent nausea and treatment-limiting nausea are different things. In REIMAGINE 2, gastrointestinal adverse events were reported in 67.2% of the 2.4/2.4 mg group, somewhat lower than the obesity trial.

Administration site reactions were reported more often with the combination than with semaglutide alone in pooled analyses, which is plausible given that two acylated peptides are being delivered in one injection. This is a difference from GLP-1 monotherapy worth noting, though it was not a major driver of discontinuation.

Beyond the trials, the broader class considerations apply: gastrointestinal effects, the theoretical and still-debated signals around gallbladder events, pancreatitis, and the rodent thyroid C-cell findings that carry a boxed warning for marketed GLP-1 products. Our overview of GLP-1 side effects covers that class-wide picture in detail. Nothing in the published CagriSema data suggests a novel safety signal unique to adding amylin, but the exposure base is still small compared with marketed GLP-1 drugs.

No peptide sold for laboratory use carries the safety characterization of a trial product manufactured under pharmaceutical conditions. Questions about handling and preparing research-grade material are addressed separately on our cagrilintide tool page, and are outside the scope of this evidence review.

As of October 2026, CagriSema is not approved anywhere. Novo Nordisk announced in December 2025 that it had submitted a New Drug Application to the United States Food and Drug Administration for once-weekly cagrilintide 2.4 mg and semaglutide 2.4 mg, to be used with a reduced-calorie diet and increased physical activity for long-term weight management in adults with obesity, or with overweight and at least one weight-related comorbidity.

The company has indicated it expects a United States decision in the fourth quarter of 2026. No public PDUFA date has been posted, so any specific date circulating online should be treated as an estimate rather than an official milestone. A decision could also take the form of a complete response letter or a request for additional information rather than an approval.

Several practical consequences follow from the unapproved status. There is no approved label, so there is no authorized indication, no approved administration schedule, and no official contraindication list for this combination. Any material sold today under the name CagriSema or as a cagrilintide plus semaglutide blend is not a pharmaceutical product, is not subject to pharmaceutical quality control, and is not covered by the trial safety data discussed above. Legal status for such materials varies substantially by jurisdiction.

It is also worth stating plainly that the REDEFINE 4 outcome described in the next section does not affect the obesity filing, which rests on REDEFINE 1 and the supporting program. A missed non-inferiority endpoint against an active comparator is a competitive problem, not a regulatory disqualification.

This section describes regulatory facts, not availability advice. If you are considering any obesity pharmacotherapy, that decision belongs with a licensed prescriber who knows your medical history.

The most informative comparison is the only direct one. REDEFINE 4 was an 84-week, open-label, head-to-head phase 3 trial in 809 adults with obesity and at least one comorbidity, with a mean baseline body weight of 114.2 kg, comparing CagriSema 2.4/2.4 mg against tirzepatide 15 mg. On February 23, 2026, Novo Nordisk announced that the trial did not meet its primary endpoint of non-inferiority to tirzepatide.

Under the efficacy analysis, mean weight loss at week 84 was 23.0% with CagriSema versus 25.5% with tirzepatide 15 mg. Under the treatment regimen analysis, the figures were 20.2% versus 23.6%. In other words, CagriSema delivered substantial weight loss in absolute terms but came in measurably behind the GIP and GLP-1 dual agonist in a direct comparison. At the time of writing, these are company-reported topline results; the full peer-reviewed publication with complete safety tables has not yet appeared.

For context on the comparator, the SURMOUNT-1 trial published in the New England Journal of Medicine in 2022 established tirzepatide's profile in obesity, with mean weight reductions of up to 20.9% at 72 weeks at the 15 mg dose in 2,539 adults without diabetes. Our tirzepatide guide covers that program in detail. Cross-trial comparisons between SURMOUNT-1 and REDEFINE 1 are unreliable because the populations, durations and estimands differ, which is exactly why REDEFINE 4 was run.

Looking further ahead, Eli Lilly reported in May 2026 that retatrutide, a triple GIP, GLP-1 and glucagon receptor agonist, produced a mean weight reduction of 28.3% at 80 weeks at the 12 mg dose in the TRIUMPH-1 phase 3 trial, with 25.9% at 9 mg and 19.0% at 4 mg. Those are company-reported figures from a different trial with its own population and design, so they establish that retatrutide is in the same upper tier rather than that it is definitively superior to anything.

The reasonable conclusion is that CagriSema sits firmly in the modern tier of highly effective obesity pharmacotherapy, that it lost its one direct comparison, and that the field's ceiling is still moving.

The largest open question is cardiovascular outcomes. REDEFINE 3 enrolled more than 7,000 participants with established cardiovascular disease and is event-driven, with completion anticipated in 2027 and a readout expected in the second half of that year. Until then, there is no outcome evidence that this combination reduces heart attacks, strokes or cardiovascular death, only surrogate improvements in weight, glycemia and blood pressure.

The second open question is whether a higher-dose version changes the competitive picture. After REDEFINE 4, Novo Nordisk indicated that a higher-dose phase 3 program would begin in the second half of 2026 and that REDEFINE 11, designed to explore the full weight-loss potential of the 2.4/2.4 mg combination, should report in the first half of 2027. Whether more amylin signaling buys more weight loss without a disproportionate tolerability cost is genuinely undetermined.

Third, durability and body composition remain thinly documented. All the pivotal data stop at 68 or 84 weeks. Weight regain after discontinuation has been observed consistently across GLP-1 based therapies, and there is no reason to assume the amylin component changes that. Lean mass preservation, bone outcomes and effects in older adults are not adequately characterized for this combination.

Fourth, nothing in the trial literature transfers to unregulated material. Published results describe a pharmaceutical-grade, fixed-dose product administered under medical supervision with monitoring and dose adjustment. Peptides sold for laboratory use are a different category entirely, with no established identity, purity, sterility or stability guarantees, and their legal status varies by country.

Finally, cost, access and long-term adherence will determine real-world impact far more than a two percentage point difference in trial means. Those are health system questions that no phase 3 trial answers.

Disclaimer: this article is for educational purposes only and does not constitute medical advice. CagriSema is an investigational product that has not been approved by the FDA or the EMA. Consult a healthcare professional before making any decision about obesity or diabetes treatment.