Amycretin is one of the more interesting molecules in Novo Nordisk's pipeline, and also one of the easiest to over-read. It is a single peptide that activates two receptors at once — the GLP-1 receptor familiar from semaglutide and the amylin receptor — and it is being developed in both an oral and a subcutaneous form. The early weight-loss figures looked large, and they were enough to move the program forward: Novo Nordisk advanced amycretin (international nonproprietary name zenagamtide) into Phase 3 development for obesity in the first quarter of 2026, with a Phase 3 program for type 2 diabetes following the same year, after a Phase 2 diabetes trial reported in late 2025 and presented at the 2026 American Diabetes Association Scientific Sessions.[4] That is a real step up in confidence from where this molecule sat a year ago — but Phase 3 is a confirmatory program, not a result, and no Phase 3 data have read out yet. Here is what the primary literature actually shows, and what it does not.
What it is: two receptors, one molecule
Amycretin is described by its developers as a novel, unimolecular GLP-1 receptor and amylin receptor agonist.[1] The GLP-1 side is well-trodden ground — it is the incretin pathway that drives appetite suppression and glucose-dependent insulin secretion. The amylin side is the newer angle. Amylin is a hormone co-secreted with insulin that promotes satiety and slows gastric emptying; amylin-receptor agonism is the mechanism behind cagrilintide, the amylin analog paired with semaglutide in CagriSema. The conceptual leap with amycretin is that instead of co-formulating two separate drugs, both actions are engineered into a single peptide. In cell-based assays that peptide activated human GLP-1, amylin and calcitonin receptors, and in diet-induced obese rats it cut body weight by about 18% over 21 days while improving insulin sensitivity and liver steatosis.[3] That is the preclinical rationale; the human data are what matter, and they are early.
The subcutaneous data (phase 1b/2a)
The most quantitatively striking read-out comes from a randomized, placebo-controlled phase 1b/2a study of once-weekly subcutaneous amycretin in adults with overweight or obesity. Between September 2023 and April 2024, 125 participants were randomly allocated to amycretin (101) or placebo (24) at a single research center, across dose-escalation arms running up to 36 weeks.[1] The estimated mean weight changes were large and dose- and duration-dependent: about −24.3% at 60 mg (week 36), −22.0% at 20 mg (week 36), −16.2% at 5 mg (week 28) and −9.7% at 1.25 mg (week 20), versus placebo changes hovering around plus-or-minus a couple of percent.[1] Those are eye-catching numbers — in the same neighborhood as the strongest injectables, including the triple agonist retatrutide.
But read the design before the headline. This was a small, single-site, early-phase study whose primary endpoint was the number of treatment-emergent adverse events, not weight.[1] The most common adverse events were gastrointestinal and mostly mild to moderate, consistent with GLP-1 and amylin agonists — and, importantly, a large number of participants withdrew, though the authors note most discontinuations were for reasons unrelated to side effects.[1] High dropout in a small trial makes any efficacy estimate fragile. These are signal-generating results, not confirmatory ones.
The oral data (phase 1)
Amycretin is also being developed as a pill, and the first-in-human oral study was published alongside the subcutaneous one. It enrolled 144 participants with overweight or obesity in a double-blind, placebo-controlled, multipart design: single ascending doses, then multiple ascending doses, then a 12-week dose-escalation part in 60 people taking oral amycretin daily at doses escalated up to 50 mg.[2] Its primary endpoint was safety — specifically the count of treatment-emergent adverse events — with pharmacokinetics as supportive secondary endpoints; body-weight change was only an exploratory endpoint over that 12-week window.[2] Adverse events were predominantly gastrointestinal and increased in a dose-dependent way, all mild or moderate, with no deaths, and the authors concluded amycretin appeared safe and tolerable and warranted further study of its weight-loss properties.[2]
So the oral story is genuinely earlier and thinner than the subcutaneous one: the trial was built to answer “is this safe and how does it behave in the body,” not “how much weight does it take off.” If an orally dosed obesity peptide pans out it would matter a great deal for access and adherence — the same reason the small-molecule oral GLP-1 orforglipron is watched so closely — but amycretin's oral efficacy simply has not been established in a powered trial yet.
The honest bottom line
Amycretin pairs a proven mechanism (GLP-1) with a fashionable one (amylin) inside a single molecule, and its early subcutaneous numbers are among the most impressive reported at this stage. That is the good news, stated precisely. A Phase 2 trial in type 2 diabetes, reported in late 2025, added to that case — the highest dose cut HbA1c by an estimated 1.71 points at 36 weeks alongside weight loss of up to 14.6% — and it was enough for Novo Nordisk to move amycretin (INN zenagamtide) into Phase 3 development for obesity in the first quarter of 2026 and for type 2 diabetes later the same year.[4] That is a genuine step beyond a single small proof-of-concept trial. The limits are still real: no Phase 3 results have read out yet, durations studied so far are measured in weeks and months rather than years, there is no long-term outcomes data, no head-to-head trial against semaglutide or the multi-agonists, and no established commercial dose. Amycretin remains investigational and is not approved anywhere. The reasonable posture has shifted from “an early signal worth watching” to “a pivotal program now underway” — genuine progress, but still a program whose defining trials have not reported. For where amycretin's unimolecular GLP-1-plus-amylin design sits against the drugs chasing the same goal by other routes — the selective amylin agonists that drop GLP-1 entirely, and the two incretin candidates that disagree about whether to switch the GIP receptor on or off — see our review of the next wave of obesity drugs.