EloraTZP: Amylin Plus Tirzepatide Hits 23.3% in Head-to-Head Trial

Research Brief — Dr. Ethan Lazarus, MD, DABOM, DABFM, MFOMA | Clinical Nutrition Center | October 9, 2026

At EASD 2026 in Milan, Eli Lilly dropped Phase 2b data on EloraTZP — a combination of eloralintide (a selective amylin receptor agonist) and tirzepatide — in 367 adults with obesity or overweight and type 2 diabetes. The headline: the top dose delivered 23.3% weight loss at 48 weeks, beating tirzepatide 15 mg alone (14.8%) inside the same trial.

That is the notable part. Head-to-head wins are uncommon in obesity medicine.

Here is what the full dose table looks like:

• Elora 3 mg + TZP 5 mg: 13.2%, −30.7 lbs, A1C −2.2%
• Elora 6 mg + TZP 5 mg: 19.4%, −45.1 lbs, A1C −2.7%
• Elora 6 mg + TZP 10 mg: 19.9%, −46.2 lbs, A1C −2.6%
• Elora 9 mg + TZP 15 mg: 23.3%, −54.1 lbs, A1C −2.9%
• TZP 15 mg alone: 14.8%, −34.4 lbs, A1C −2.4%
• Eloralintide 3 mg alone: 8.2%, −19.1 lbs, A1C −1.1%
• Discontinuation ran 10.8% to 27.0% across the four combination arms. The 23.3% uses the efficacy estimand — it assumes everyone stayed on treatment. At the upper end of that range, roughly one in four participants did not finish.
• Three things worth stating plainly. First, this was Phase 2b dose-finding. Results routinely shift in confirmatory trials. Second, EloraTZP requires two separate injections, not one — a meaningful difference for anyone who has been on injectable obesity medications. Third, the head-to-head versus tirzepatide alone was a secondary endpoint. The primary compared EloraTZP to placebo.
• The mechanism is genuinely new. Amylin acts on a different receptor pathway than GLP-1 or GIP. CagriSema (Novo Nordisk) uses the same amylin idea and was covered here in September — this is an industry trend, not a one-off. The amylin story is real, and it is moving fast.
• Eloralintide alone produced 8.2%. The 23.3% comes from stacking it onto tirzepatide 15 mg — the best available dose of a drug that already works. That is combination arithmetic as much as it is a new mechanism.
• Neither eloralintide nor EloraTZP is approved. Phase 3 starts Q4 2026. The timeline to a pharmacy is years.
• Worth noting who was studied. Every participant had both obesity and type 2 diabetes. That important for my Greenwood Village patients who are already on a GLP-1 or a tirzepatide. The question this raises is not ”should I try this.” It is whether the next generation will be a second injection stacked on the first.
• Clinical takeaway: For patients with type 2 diabetes and obesity already on or considering tirzepatide, the amylin pathway represents a plausible next step. But wait for Phase 3 data, weigh the two-injection burden, and watch the discontinuation rates closely before extrapolating the efficacy estimand to real-world expectations.

— Dr. Lazarus
Clinical Nutrition Center
Greenwood Village, Colorado

Frequently Asked Questions

What is EloraTZP?

EloraTZP is an investigational combination of two drugs given as separate injections: eloralintide, a selective amylin receptor agonist, and tirzepatide, the dual GIP and GLP-1 receptor agonist sold as Zepbound and Mounjaro. By targeting the amylin and incretin pathways together, the combination is designed to work through two separate appetite and metabolic mechanisms at once. Neither component is approved for this use.

How much weight did people lose on EloraTZP?

In the 48-week Phase 2b trial of 367 adults with obesity or overweight and type 2 diabetes, the highest dose combination of eloralintide 9 mg plus tirzepatide 15 mg produced an average weight loss of 23.3%, or 54.1 pounds, from a mean baseline weight of 105.4 kg. Lower combinations ranged from 13.2% to 19.9%. For comparison in the same trial, tirzepatide 15 mg alone produced 14.8%, and eloralintide 3 mg alone produced 8.2%.

Did EloraTZP beat Zepbound in the same trial?

It beat tirzepatide 15 mg within the same study, which is unusual in obesity medicine. However, that head-to-head comparison was a secondary endpoint. The trial’s primary endpoint compared EloraTZP against placebo. The trial did not test the combination against any other investigational drug, so no comparison with retatrutide or any other candidate is valid.

Is EloraTZP available to patients?

No. EloraTZP and eloralintide are investigational and have not been approved by the FDA or any other regulator. Eli Lilly plans to begin Phase 3 trials in Q4 2026, and separately is studying eloralintide on its own in several Phase 3 trials under the ENLIGHTEN programme. Confirmatory trials often produce different results than dose-finding studies, and approval typically follows several years of further study.

What should patients know about tolerability?

Treatment discontinuation ranged from 10.8% to 27.0% across the four combination arms. The headline 23.3% figure uses what trial researchers call the efficacy estimand, which assumes every participant stayed on treatment and so excludes people who discontinued. At the upper end of that discontinuation range, roughly one in four participants did not complete the trial. Those two figures together give a more realistic picture than the headline number alone.