Novo Nordisk disclosed the result of its second head-to-head against tirzepatide on August 5, 2026, alongside Q2 earnings — and it was a split verdict. In REIMAGINE 4, a 68-week trial in roughly 1,000 adults with type 2 diabetes, CagriSema matched tirzepatide 15 mg on weight reduction but failed to match it on blood sugar control. CagriSema delivered 15.2% weight loss and a 1.9 percentage-point HbA1c reduction; non-inferiority was met for weight, missed for HbA1c.
That is a meaningfully different outcome from the obesity head-to-head six months earlier, where CagriSema lost on the weight endpoint outright. Read side by side, the two trials sketch a clearer picture of what adding an amylin analog to semaglutide actually buys you — and where tirzepatide still holds an edge.
Research-context information only. This article reports clinical trial data and what it means for people evaluating these compounds. It is not medical advice and not a protocol recommendation. CagriSema is an investigational combination that is not FDA-approved. Cagrilintide is not approved for human use in any market; research-grade compounds are sold for laboratory research purposes only. Talk to a licensed physician before starting any GLP-1 or amylin protocol.
What REIMAGINE 4 Tested
REIMAGINE 4 is the head-to-head arm of Novo's diabetes program for CagriSema — a once-weekly fixed-dose combination of cagrilintide 2.4 mg, a long-acting amylin analog, and semaglutide 2.4 mg.
The design was an open-label, 68-week Phase 3 trial in approximately 1,000 adults with type 2 diabetes inadequately controlled on metformin, with or without an SGLT2 inhibitor. Participants received either CagriSema 2.4 mg/2.4 mg or tirzepatide 15 mg — the highest approved tirzepatide dose, and the same comparator arm Novo chose for the obesity trial.
The reported outcomes for the CagriSema arm:
| Endpoint | CagriSema 2.4/2.4 mg | Versus tirzepatide 15 mg |
|---|---|---|
| Body weight reduction (68 wk) | 15.2% | Non-inferiority met |
| HbA1c reduction (68 wk) | 1.9 percentage points | Non-inferiority not met |
Novo disclosed the topline in its Q2 2026 results and on the accompanying earnings call. Arm-by-arm figures for the tirzepatide group were not broken out in that disclosure — full data are expected at a future scientific congress, which is the same sequence the company followed with the REIMAGINE 1-3 trials before presenting them at ADA in June 2026.
Two framing notes matter for reading these numbers. First, "non-inferiority met" is not "superiority" — it means the two treatments were statistically comparable on that endpoint, not that CagriSema won. Second, this was a diabetes cohort. People with type 2 diabetes reliably lose less weight on every GLP-1 than non-diabetic participants do, which is why 15.2% here sits well below the 20-23% CagriSema produced in obesity trials.
The Two Head-to-Heads Tell Opposite Halves of the Story
This is the second time CagriSema has been run directly against tirzepatide 15 mg, and the results point in different directions depending on the population.
| Trial | Population | Duration | CagriSema | Tirzepatide 15 mg | Primary endpoint |
|---|---|---|---|---|---|
| REDEFINE 4 (Feb 2026) | Obesity, 809 adults | 84 weeks | 23.0% weight loss | 25.5% weight loss | Non-inferiority on weight missed |
| REIMAGINE 4 (Aug 2026) | Type 2 diabetes, ~1,000 adults | 68 weeks | 15.2% weight loss | Not disclosed | Non-inferiority on weight met, HbA1c missed |
In obesity, CagriSema trailed tirzepatide by about 2.5 percentage points of body weight and missed its endpoint. In diabetes, it closed that weight gap — but gave ground on glycemic control instead.
The mechanistic read is reasonably clean. Tirzepatide's second receptor is GIP, an incretin that acts directly on glucose-dependent insulin secretion. Cagrilintide's contribution is amylin signaling, which works on satiety and gastric emptying rather than on insulin release. So a combination built on appetite suppression can pull level on weight, while a molecule with a second incretin arm keeps the advantage on HbA1c. That is roughly what both trials show.
For anyone evaluating these compounds primarily for body composition rather than glucose management, the missed endpoint here is the less relevant of the two — REIMAGINE 4's weight result is the one that landed. For anyone whose main concern is blood sugar, tirzepatide came out of this trial ahead.
What This Means for Buyers
There is no CagriSema to buy. It is a single fixed-dose combination product that has not been approved anywhere; Novo reiterated on the call that it expects a US regulatory decision in obesity at the end of 2026, with a potential launch in 2027. Nothing in REIMAGINE 4 changes that timeline, since the obesity filing rests on the REDEFINE program.
What is available today are the individual compounds, sold as research-grade material by vendors that publish batch-specific COAs.
One caveat belongs ahead of any of that, though. REIMAGINE 4 tested a fixed-dose combination manufactured as a single product, not two vials drawn and mixed by hand. Trial results from a co-formulated product do not transfer cleanly to separately sourced components, where dose ratios, purity, and stability all vary by vendor and batch. Nothing in this readout should be treated as evidence about what individually sourced material does. Our cagrilintide buying guide covers COA verification and current vendor pricing in detail.
With that framing in place, the compounds referenced above:
- Best Tirzepatide Vendors — the dual GLP-1/GIP agonist studied as the comparator arm in both head-to-heads. Live $/mg across 10mg, 30mg, and 60mg vials.
- Best Cagrilintide Vendors — the amylin analog half of the combination, thinner vendor coverage and wider price spread than the GLP-1s.
- Best Semaglutide Vendors — the GLP-1 half, and the most widely stocked compound on the list.
- All Active Vendor Coupons — current discount codes across recommended vendors.
