Cagrilintide: The Amylin Analog, Explained

Semaglutide and tirzepatide get most of the attention in obesity medicine, but Novo Nordisk’s next candidate works on a different hormone entirely. Cagrilintide mimics amylin, a satiety signal that the pancreas normally releases alongside insulin, and the company is testing it both alone and paired with semaglutide in a combination called CagriSema. Here’s what amylin actually does, why pairing it with a GLP-1 drug is biologically plausible, and how far along the evidence really is.

What Amylin Does in the Body

Amylin (also called islet amyloid polypeptide) is a small peptide hormone co-secreted with insulin by the beta cells of the pancreas every time you eat. It doesn’t do the same job as insulin. Instead, amylin acts mainly in the brain, at a hindbrain structure called the area postrema, where it signals fullness, slows the rate at which the stomach empties into the small intestine, and suppresses glucagon (a hormone that raises blood sugar). In effect, amylin is part of the body’s short-term “stop eating” and “slow down digestion” circuitry — a distinct system from the GLP-1 pathway, even though the two produce some overlapping effects.

People with type 2 diabetes, and to some extent people with obesity, tend to have disrupted amylin signaling, which is one reason researchers have looked at amylin analogs as a treatment target for decades — long before GLP-1 drugs became mainstream.

From Pramlintide to Cagrilintide

Amylin analogs aren’t new. Pramlintide (brand name Symlin) is a short-acting amylin analog that has been FDA-approved since 2005, used alongside insulin in some people with type 1 or type 2 diabetes to help manage post-meal blood sugar spikes. Its major limitation is pharmacokinetic: it has a short half-life and requires injections at mealtimes, which makes it inconvenient and has kept it a niche drug.

Cagrilintide is Novo Nordisk’s attempt to fix that problem using the same chemistry trick that made semaglutide viable as a once-weekly injection: attaching a fatty-acid side chain that binds to albumin in the blood, slowing the drug’s clearance. The result is an amylin analog that, like semaglutide, can be dosed roughly once a week instead of multiple times a day.

Why Pair an Amylin Analog With a GLP-1 Drug?

The rationale for combining cagrilintide with semaglutide (the combination is called CagriSema) is that the two hormones act on different, complementary circuits. GLP-1 receptor agonists work partly through the hypothalamus and vagal afferents to reduce appetite and slow gastric emptying; amylin analogs work substantially through the area postrema, a separate hindbrain satiety center. Preclinical work in animal models has suggested that hitting both pathways at once can produce greater appetite suppression and weight loss than either hormone alone, which is the basic logic behind testing the combination in humans.

The idea behind CagriSema is sound biology, but “sound biology” and “proven in large, long-term human trials” are not the same thing — and right now, cagrilintide’s evidence base is thinner than semaglutide’s.

Where the Clinical Evidence Actually Stands

Cagrilintide alone was tested in a phase 2, dose-finding trial (Lau et al., published in The Lancet in 2021) that compared it against placebo and against liraglutide in adults with overweight or obesity. That trial reported meaningful weight loss with cagrilintide monotherapy relative to placebo, though less than what’s typically seen with the more potent GLP-1 drugs used today.

The bigger story is CagriSema’s phase 3 program, known as REDEFINE. Novo Nordisk has reported topline results from multiple REDEFINE trials: one in adults with obesity or overweight but without type 2 diabetes, and another in adults with both obesity and type 2 diabetes. In the non-diabetes trial, the company reported average weight loss of roughly one-fifth to one-quarter of body weight after about 68 weeks — substantial, though below what some analysts had expected given the combination’s mechanism. In the diabetes trial, reported weight loss was noticeably smaller, in the low-to-mid teens as a percentage of body weight, consistent with the broader pattern seen across GLP-1 drugs: weight loss tends to be blunted in people who have diabetes.

It’s worth being clear about what this evidence is and isn’t. These are company-reported topline results, not yet fully published, peer-reviewed papers with complete safety data. That matters for a class of drug this new.

How the Amylin-Pathway Drugs Compare

Drug	Hormone mimicked	Dosing	Regulatory status
Pramlintide (Symlin)	Amylin	Multiple daily injections	FDA-approved (2005), used with insulin in diabetes
Cagrilintide (alone)	Amylin	Once weekly	Investigational; phase 2/3 data only
Semaglutide (Ozempic/Wegovy)	GLP-1	Once weekly	FDA-approved
CagriSema (cagrilintide + semaglutide)	Amylin + GLP-1	Once weekly, combined	Investigational; phase 3 (REDEFINE) reported, not yet approved

Safety and Open Questions

Amylin analogs share much of the GI side-effect profile seen with GLP-1 drugs — nausea, vomiting, and reduced appetite are common in trials. Because pramlintide has historically been paired with insulin, there’s also a known hypoglycemia risk in that combination; whether that risk carries over to cagrilintide or CagriSema in people without diabetes is still being worked out. Longer-term questions — durability of weight loss, what happens after stopping the drug, and cardiovascular outcomes — simply haven’t been answered yet for this molecule, unlike semaglutide, which now has years of outcomes data behind it.

The Takeaway

Cagrilintide represents a genuinely different mechanism, not just another GLP-1 drug with a new name, and the biological logic for pairing it with semaglutide is reasonable. But it is still investigational: the strongest data so far are company-reported trial results awaiting full publication, and neither cagrilintide alone nor CagriSema is FDA-approved as of this writing. Anyone curious about it should treat it as a drug to watch, not one to seek out — and any decision about obesity or diabetes treatment, including whether to wait for a newer option or start with an approved one, belongs with a clinician.

Sources

• Lau DCW, et al. “Once-weekly cagrilintide for weight management in obesity: a phase 2 trial.” The Lancet, 2021 — PubMed
• Novo Nordisk — CagriSema and the company’s obesity pipeline
• FDA Drugs@FDA database — pramlintide (Symlin) approval and label information
• PubMed — amylin physiology, satiety signaling, and gastric emptying