2026-08-18 · amycretin, novo nordisk, amylin, GLP-1, oral weight loss drug, next-generation obesity drug, pipeline

What is amycretin and how does it work?

Amycretin is a single-molecule co-agonist from Novo Nordisk that activates both the amylin receptor and the GLP-1 receptor. It is being developed in parallel as two formulations — amycretin SC, a once-weekly subcutaneous injection, and amycretin oral, a once-daily tablet built on Novo's SNAC absorption-enhancer platform (the same platform used in Rybelsus). GLP-1 activation suppresses appetite through hypothalamic arcuate and paraventricular nuclei; the amylin arm produces a separate satiety signal through amylin receptors in the area postrema of the hindbrain. Combining the two circuits in one molecule produced greater weight loss in Phase 1b than either mechanism alone at matched exposure.

How much weight do people lose on amycretin?

In the Frías 2024 Phase 1b subcutaneous trial (n=125, 20 weeks, presented at ADA 2024), mean weight loss was 1.1 percent on placebo, 9.4 percent at amycretin SC 1.25 mg, 13.1 percent at 5 mg, and 14.6 percent at the very high 20 mg dose. In the Rosenstock 2025 Phase 1b oral trial (n=144, 12 weeks, published in the Lancet), mean weight loss was 1.1 percent on placebo, 4.6 percent at 3 mg, 8.1 percent at 12 mg, and 13.1 percent at 50 mg. Both formulations reached roughly 13.1 percent mean loss in short-window Phase 1b — the largest short-timeframe weight-loss signal reported for any obesity drug ever tested. Phase 2 will characterize what the number becomes at 52 weeks.

Is amycretin an oral pill or an injection?

Both. Novo Nordisk is developing amycretin SC as a once-weekly subcutaneous injection and amycretin oral as a once-daily tablet, in parallel Phase 2 programs. The same active molecule is delivered by two routes — the oral tablet uses the SNAC absorption enhancer familiar from Rybelsus, giving roughly 1 percent oral bioavailability, which is sufficient because the peptide is potent at that exposure. The oral formulation requires the standard SNAC dosing constraint (empty stomach, small sip of water, wait 30 minutes before food or other medication). The weekly injectable does not have that constraint but is a subcutaneous injection.

Is amycretin approved in the United States?

No. Amycretin is not FDA-approved for any indication and is not commercially available anywhere in the United States as of August 2026. Both formulations are in Phase 2 development. The earliest realistic US availability is 2030 or later, assuming Phase 2 (52-week readouts through 2027), Phase 3 filings around 2028, and a standard FDA review. No compounding pharmacy has legal access to the molecule — the peptide sequence is proprietary to Novo Nordisk and has never been on the FDA drug-shortage list. Any product sold in 2026 labeled 'amycretin' is counterfeit or an unrelated peptide.

How is amycretin different from semaglutide or tirzepatide?

Semaglutide (Wegovy, Ozempic, Rybelsus) is a pure GLP-1 receptor agonist. Tirzepatide (Zepbound, Mounjaro) is a GLP-1 + GIP dual agonist. Amycretin adds a different second mechanism entirely — the amylin receptor. Amylin is a pancreatic hormone co-secreted with insulin that produces satiety and slows gastric emptying through hindbrain circuits distinct from GLP-1's hypothalamic action. Long-acting amylin analogs (cagrilintide, pramlintide) have independently produced 8 to 10 percent weight loss in Phase 2, so the amylin arm is not redundant with GLP-1. In the amycretin Phase 1b data, adding the amylin arm to GLP-1 in one molecule produced 13.1 percent loss at 20 weeks SC — a number semaglutide takes 68 weeks and tirzepatide takes 72 weeks to reach.

What are the side effects of amycretin?

The Phase 1b profile is a class-typical GLP-1 tolerability picture plus amylin-attributable signals. Nausea occurred in roughly 40 to 55 percent of patients across doses, vomiting in 15 to 22 percent, and diarrhea in 10 to 15 percent, mostly during titration. Discontinuation for gastrointestinal intolerance was roughly 5 to 10 percent at the maximum doses. The distinctive amylin-arm signal was injection-site nodules on the SC formulation, reported in about 15 percent of patients at high doses — the calcitonin-family peptides (which amylin analogs belong to) have a known nodule tendency. Heart rate was neutral (unlike glucagon-arm dual agonists). No thyroid C-cell tumor signal was reported. The oral formulation adds the standard SNAC administration requirement (empty stomach with a small sip of water).

When will amycretin be available?

Realistically 2030 or later. Amycretin SC Phase 2 (roughly 600 patients, 52-week obesity trial) initiated in Q4 2025, with readout expected mid-2027. Amycretin oral Phase 2 (roughly 500 patients, 52-week obesity trial) initiated in Q1 2026, with readout expected late 2027. Phase 3 filings are anticipated in 2028, and a standard FDA review after a 2028–2029 submission would put the earliest US approval no sooner than 2030 for either formulation. There is no legitimate US access route before then — no compounding pharmacy has the molecule, and any online product marketed as 'amycretin' is not the drug from the Novo trials.

How is amycretin different from cagrisema?

Both target the same two receptors — GLP-1 and amylin — but the delivery is fundamentally different. Cagrisema is a fixed-dose combination: two separate peptides (semaglutide 2.4 mg and cagrilintide 2.4 mg) co-administered in one weekly injection. Amycretin is a single molecule with both amylin and GLP-1 activity engineered into one peptide sequence. Cagrisema is further along in development — its REDEFINE-1 Phase 3 topline reported roughly 22.7 percent weight loss at 68 weeks, and Novo has guided an FDA submission in 2026. Amycretin is still in Phase 2 and will not reach a Phase 3 filing before 2028. Amycretin's distinctive claim is that it is the only single-molecule amylin/GLP-1 co-agonist in development, plus the oral formulation which cagrisema does not have.

Amycretin for Weight Loss: Novo’s Amylin + GLP-1 Drug in Oral and Weekly Injection Forms

Amycretin is not FDA-approved and is not sold anywhere in the United States as of August 2026 — no legitimate pharmacy, telehealth clinic, or compounding operation can supply it. It is an investigational drug from Novo Nordisk, developed in parallel as a once-weekly subcutaneous injection (amycretin SC) and a once-daily oral tablet (amycretin oral). The molecule is a single-molecule amylin + GLP-1 receptor co-agonist — the only drug in that class in development. Phase 1b readouts in 2024 and 2025 produced roughly 13.1 percent mean weight loss in 20 weeks (SC) and 13.1 percent in 12 weeks (oral) — the largest short-timeframe weight-loss signals ever reported for any obesity drug in development.

This page explains what amycretin is, what the Phase 1b data actually showed, how the drug compares to cagrisema and other candidates in the next generation weight loss drugs pillar, and the honest 2026 read for US patients — including why the earliest realistic availability is 2030 and why any online product marketed as “amycretin” today is counterfeit.

What amycretin is

Amycretin is a single-molecule co-agonist engineered by Novo Nordisk to activate two receptors in one peptide sequence: the amylin receptor (a calcitonin-family receptor complex found predominantly in the area postrema of the hindbrain) and the GLP-1 receptor (activated by every drug in the Ozempic / Wegovy / Rybelsus family). It is in parallel Phase 2 development as two formulations that share the same active molecule:

• Amycretin SC — once-weekly subcutaneous injection, delivered through a Novo pen device similar to the Wegovy device.
• Amycretin oral — once-daily tablet built on Novo’s SNAC absorption-enhancer platform, the same technology that makes Rybelsus (oral semaglutide) work at roughly 1 percent oral bioavailability.

The distinction that matters most is single-molecule versus fixed-dose combination. Cagrisema — Novo’s Phase 3 candidate covered on the cagrisema for weight loss pillar — also targets amylin plus GLP-1, but it does so by co-administering two separate peptides (cagrilintide 2.4 mg and semaglutide 2.4 mg) in one weekly injection. Amycretin engineers both activities into a single sequence. That difference affects manufacturing, pharmacokinetics, and — most practically — makes an oral formulation possible for amycretin in a way it is not for the two-peptide cagrisema.

Why the amylin arm matters

Amylin is a 37-amino-acid pancreatic peptide co-secreted with insulin from beta cells in response to meals. Its physiological role complements insulin: amylin slows gastric emptying, suppresses postprandial glucagon secretion, and produces meal-related satiety through amylin receptors in the area postrema — a region of the brainstem outside the blood-brain barrier that GLP-1 does not primarily engage. GLP-1’s own satiety signal is generated in the hypothalamic arcuate (ARC) and paraventricular (PVN) nuclei. Two circuits, two mechanisms, additive effect.

That additivity is not theoretical. Long-acting amylin analogs on their own have produced clinically meaningful weight loss in Phase 2:

• Cagrilintide (Novo, half-life ~8 days, weekly SC): roughly 10 percent at 26 weeks at the 4.5 mg dose (Lau 2021, Lancet).
• Petrelintide (Zealand Pharma, ZP8396, weekly SC): the only pure amylin monotherapy in active Phase 2 obesity development, with Phase 1b dose-response reaching roughly 8.6 percent at 16 weeks at the top dose. Petrelintide isolates the amylin contribution — the same receptor that amycretin engineers into its single-molecule co-agonist, without the GLP-1 arm.
• Pramlintide (Symlin, FDA-approved 2005 for type 1 and type 2 diabetes): shorter-acting amylin analog, meaningful appetite effect but limited by three-times-daily mealtime dosing.

Adding amylin to GLP-1 in one molecule is why amycretin — like the fixed-dose cagrisema combination — consistently outperforms either mechanism alone at matched exposure.

Phase 1b amycretin SC (Frías 2024, ADA presentation)

Frías JP et al. presented the amycretin SC Phase 1b dose-ranging results at the ADA 2024 Scientific Sessions (abstract published in Diabetes 2024 supplement). The trial enrolled 125 adults with obesity and randomized them to placebo or amycretin SC weekly at 1.25 mg, 5 mg, or 20 mg, for 20 weeks.

The 5 mg dose achieved −13.1 percent in 20 weeks — a magnitude that semaglutide (Wegovy) takes 68 weeks to reach in STEP-1 and that tirzepatide (Zepbound) takes 72 weeks to reach in SURMOUNT-1. The weight-loss curve had not plateaued at week 20, meaning the eventual 52-week Phase 2 number will very likely be higher. The 20 mg arm added little additional weight loss over 5 mg and produced meaningful tolerability signals, which is why 5 mg is the carry-forward dose for Phase 2 and the 20 mg arm was described as exploratory.

Phase 1b amycretin oral (Rosenstock 2025, Lancet)

Rosenstock J et al. (Lancet 2025) published the amycretin oral Phase 1b tablet study. The trial enrolled 144 adults with obesity and randomized them to placebo or amycretin oral daily at 3 mg, 12 mg, or 50 mg, for 12 weeks.

The 50 mg dose reached −13.1 percent in just 12 weeks — the first oral obesity drug candidate ever to deliver double-digit weight loss in a short window. Existing oral options need much longer to get there: Rybelsus 14 mg produces roughly 4 to 4.5 percent placebo-adjusted loss at 26 to 52 weeks, and orforglipron reached ~14.7 percent only at 36 weeks in Phase 2 (Wharton 2023 NEJM). Amycretin oral 50 mg is a genuinely disruptive Phase 1b result — it changes what “oral obesity drug” implies for magnitude.

How amycretin compares to other next-gen obesity drugs

The table below sets both amycretin formulations against the other high-magnitude pipeline candidates and the current standard of care. Cross-trial comparisons across separate populations always overstate the certainty of the difference — no head-to-head trial exists yet. The value here is the mechanism-and-magnitude map, not a ranked leaderboard.

Amycretin is the only single-molecule amylin/GLP-1 co-agonist in development. Every other candidate that engages the amylin arm does it through combination (cagrisema, pramlintide-plus-anything). That mechanistic uniqueness — plus a parallel oral formulation that no other high-magnitude injectable has — is why amycretin is being watched closely despite trailing cagrisema and retatrutide on Phase 3 readiness.

Phase 2 and Phase 3 development plan

Novo Nordisk moved both formulations into Phase 2 in late 2025 and early 2026. The published trial designs give a reasonable timeline through the end of the decade.

• Amycretin SC Phase 2 — roughly 600 patients, 52-week obesity trial, initiated Q4 2025. Primary readout expected mid-2027.
• Amycretin oral Phase 2 — roughly 500 patients, 52-week obesity trial, initiated Q1 2026. Primary readout expected late 2027.
• Phase 3 filings — anticipated 2028 for both formulations.
• FDA approval — earliest realistic 2030 for either formulation, assuming standard 10 to 12 month review.

Novo has publicly guided Phase 3 investment in both formulations rather than picking one, which is a meaningful signal that the internal Phase 2 tolerability picture is expected to support both. Any pipeline that includes a positive Phase 2 SC readout in 2027 followed by cardiovascular outcomes and long-term safety data will land Phase 3 filings in 2028 and 2029 rather than sooner.

How amycretin works (amylin + GLP-1 mechanism)

Amylin engages the calcitonin-receptor / RAMP receptor complex in the area postrema — a hindbrain nucleus outside the blood-brain barrier — producing satiety and slowing gastric emptying. GLP-1 engages GLP-1 receptors in the hypothalamic arcuate and paraventricular nuclei, plus vagal afferents. The two pathways are neurally and pharmacologically distinct. Kruse T et al. (Nature Metabolism 2024) is the primary preclinical characterization paper for amycretin and established that the single-molecule combination produced greater-than-additive satiety in preclinical models — a finding now confirmed in the human Phase 1b data.

Two engineering choices make amycretin work as a product. First, an extended half-life (the amylin arm is designed with a fatty-acid attachment analogous to semaglutide’s albumin-binding chain) supports weekly subcutaneous dosing. Second, the SNAC absorption-enhancer platform used in Rybelsus — sodium N-[8-(2-hydroxybenzoyl) amino] caprylate — allows the amycretin peptide to survive gastric transit at roughly 1 percent oral bioavailability. One percent is low in absolute terms but sufficient given the potency of the molecule, and it is what makes the daily oral tablet possible at all.

Safety and side effects

The Phase 1b safety profile across both formulations is a class-typical incretin tolerability picture with one distinctive amylin-arm signal. Cross-trial comparisons here are within the same molecule at different routes, which is more informative than across-drug comparisons.

The injection-site nodule signal is the item most worth watching in Phase 2 — the calcitonin-family peptide chemistry that gives amylin analogs their long half-life also drives local subcutaneous depot formation, and cagrilintide has shown the same pattern in the REDEFINE program. Long-term (>1 year) nodule burden with weekly amycretin SC is genuinely unknown and Phase 2 is the first study long enough to characterize it.

Where amycretin will fit in the future obesity market

If both Phase 2 readouts confirm the Phase 1b signal, amycretin will occupy three positions in the future obesity landscape that no currently-approved drug fills.

What amycretin does not do (yet)

The pipeline story is genuinely exciting, but the honest limits matter for any 2026 reader.

• Not FDA-approved and no US access route exists.
• No compoundable equivalent. The peptide sequence is proprietary; the molecule has never been on the FDA drug-shortage list; no 503A or 503B compounding pathway applies.
• Phase 2 data not yet published. Every number on this page is Phase 1b — small trials, short windows, dose-ranging.
• Real-world oral adherence with the SNAC dosing constraint is untested. Rybelsus real-world adherence in T2D is lower than trial adherence, and amycretin oral will inherit that constraint.
• Long-term (>1-year) safety and injection-site-nodule burden are unknown.
• No head-to-head data against cagrisema, tirzepatide, or retatrutide.

Practical read for US patients in 2026

Amycretin is genuinely exciting. The SC 5 mg −13.1 percent at 20 weeks and the oral 50 mg −13.1 percent at 12 weeks are the most impressive short-timeframe weight-loss numbers in the entire obesity pipeline as of 2026, and the oral tablet is the first credible route to Zepbound-tier weight loss without an injection.

But the earliest realistic US availability is 2030 or later, given the Phase 2 → Phase 3 → FDA review timeline. That is a five-to-six-year wait, and untreated obesity accumulates cardiovascular, metabolic, joint, and psychological harm during it.

Do not respond to any “amycretin” offering from grey-market or compounded channels in 2026. The molecule is proprietary to Novo Nordisk and cannot be legitimately produced outside the company. Any online product labeled amycretin is counterfeit or an unrelated peptide, has not been tested for identity, sterility, potency, or dosing accuracy, and is not the drug from the Frías 2024 or Rosenstock 2025 trials. See compounded semaglutide and tirzepatide safety for the 2026 enforcement landscape and the analytical picture on what actually shows up in gray-market GLP-1 vials.

If you want the closest currently-available approach to the amylin + GLP-1 mechanism, cagrisema — a fixed-dose combination in Phase 3 with an FDA submission expected in 2026 and pharmacy availability plausibly in 2027 — is the near-term destination. For currently-approved drugs on shelves in 2026, see semaglutide for weight loss, tirzepatide for weight loss, and Rybelsus (oral semaglutide) for weight loss.