Eli Lilly's EloraTZP, its investigational amylin drug eloralintide taken with tirzepatide, produced up to 23.3% average weight loss over 48 weeks in adults with obesity and type 2 diabetes. Tirzepatide 15 mg alone, the top dose of Mounjaro and Zepbound, produced 14.8%. The phase 2 results were presented on 30 September 2026 at the EASD meeting in Milan by Dr Liana Billings of Endeavor Health.
What happened
The trial (NCT06603571) enrolled 367 adults with obesity or overweight and type 2 diabetes in the United States and Argentina. On average they weighed 105.4 kg and had an A1C of 8.1%. They were split between placebo, eloralintide alone, tirzepatide 15 mg alone, and four combinations, for 48 weeks. Doses were raised in steps, and in some combination groups eloralintide was not started until week 24.
Amylin is a hormone released alongside insulin after you eat, and it helps signal fullness. Tirzepatide acts on two gut hormone receptors, GIP and GLP-1. Combining the two is the same idea behind Novo Nordisk's CagriSema.
| Treatment | Weight lost | A1C fall |
|---|---|---|
| Placebo | 3.0% | 0.3 |
| Eloralintide alone, 3 to 9 mg | 8.2% to 12.3% | 1.1 to 1.4 |
| Tirzepatide 15 mg alone | 14.8% | 2.4 |
| Eloralintide 3 mg + tirzepatide 5 mg | 13.2% | 2.2 |
| Eloralintide 6 mg + tirzepatide 5 mg | 19.4% | 2.7 |
| Eloralintide 6 mg + tirzepatide 10 mg | 19.9% | 2.6 |
| Eloralintide 9 mg + tirzepatide 15 mg | 23.3% | 2.9 |
These are efficacy estimand figures: what Lilly estimates would happen if everyone had stayed on treatment. On the top combination, the average loss was 24.6 kg.
What about side effects?
Lilly reports that side effects were mostly gastrointestinal, mostly mild or moderate, and came mainly during dose increases. They were more common on the combinations than on either drug alone.
The number that matters most is who stopped. Between 10.8% and 27.0% of people on the combinations stopped treatment because of side effects, against 2.9% on tirzepatide 15 mg alone and 0% to 10.8% on eloralintide alone. Lilly says its phase 3 trials will use an optimised dose escalation schedule. One oddity: 16.7% of people on placebo also stopped for side effects, more than on tirzepatide.
What it does not tell us
- Results for people without diabetes. This trial was in type 2 diabetes only.
- The full picture. As of October 2026 the results are a congress presentation and a company release, not a peer-reviewed paper.
- Small groups. 367 people split across this many arms means each group was small, so single figures carry real uncertainty.
- What the loss was made of. No body composition data was reported.
- What happens past 48 weeks.
What it means for you
If you take Mounjaro or Zepbound now, nothing changes. Eloralintide is not approved anywhere, and Lilly has said phase 3 trials are planned to start in the last quarter of 2026. Never add another weight loss medicine, including anything sold online as an amylin drug, without your prescriber.
The more useful point is about the drug you may already take: in this trial tirzepatide 15 mg alone gave 14.8% in people with type 2 diabetes. If your own loss is in that range, it is in line with the trial, not a failure. For eating well on it, see what to eat on Mounjaro.
What to do with this
The bigger the loss and the smaller the appetite, the more each meal has to carry. Set a daily protein target from your body weight and build meals around it before the rest of the plate.