🧬 EloraTZP Beats Tirzepatide: 23.3% Weight Loss
Lilly paired tirzepatide with eloralintide, an amylin agonist, in a phase 2b trial in type 2 diabetes — and the combination left tirzepatide alone far behind on both weight and blood sugar.
Eli Lilly has released phase 2b results for EloraTZP, its investigational combination of eloralintide and tirzepatide, tested head-to-head against tirzepatide 15 mg alone in 367 adults living with obesity or overweight and type 2 diabetes. Every dose combination studied met its primary and secondary endpoints. At the highest combination — 9 mg of eloralintide with 15 mg of tirzepatide — participants lost an average of 23.3% of their body weight over 48 weeks, or 54.1 pounds. Tirzepatide alone, the strongest approved therapy in its class, delivered 14.8%, or 34.4 pounds.
The new ingredient is eloralintide, a selective amylin receptor agonist. Amylin is a hormone released alongside insulin after meals: it slows gastric emptying, promotes satiety in the brain, and smooths post-meal glucose. Tirzepatide already works two pathways at once — GLP-1 and GIP. Adding amylin brings a third, distinct pathway to the same meal-response system, and the glycemic numbers moved with the weight: A1C fell by up to 2.9 percentage points on the combination, against 2.4 points on tirzepatide alone.
🧩 Three pathways, one meal response
GLP-1
Appetite and insulin signaling — one half of tirzepatide's dual action.
GIP
The second incretin — tirzepatide's metabolic partner pathway.
Amylin
Slows gastric emptying, promotes satiety in the brain, and smooths post-meal glucose.
EloraTZP = tirzepatide's two pathways, plus amylin — the third.
📈 The 48-week gap
Average weight loss at 48 weeks (%)
Lines connect baseline with the reported 48-week endpoints; interim timepoints were not published with the release.
Context matters here: weight loss in type 2 diabetes trials generally runs below what the same drugs achieve in obesity-only populations, because diabetes itself resists weight loss. A 23.3% average in a diabetes population is the kind of number that, until now, belonged to bariatric surgery conversations. Lead investigator Liana K. Billings of Endeavor Health put the patient view plainly in Lilly's release:
⚖️ Honest caveats
- These are company-presented results — a Lilly news release with data presented at EASD on September 30, 2026 — not yet peer-reviewed or published in a journal.
- Gastrointestinal side effects were the most frequent, and they occurred more often in the combination arms than on tirzepatide alone.
- Between 10.8% and 27% of participants in the combination arms stopped treatment — tolerability, and the dose-escalation schedule, are the open questions phase 3 has to answer.
- The trial ran 48 weeks in people with type 2 diabetes; results in other populations, and beyond 48 weeks, are not yet known.
What happens next: Lilly plans to advance a co-formulated version of EloraTZP — the two drugs in a single product — into phase 3 trials by late 2026, using an optimized dose-escalation regimen aimed squarely at the tolerability problem. What to watch is whether the phase 3 program holds the eight-and-a-half-point gap over tirzepatide while bringing discontinuations down. If it does, the multi-hormone era stops being a pipeline story and becomes the standard of care.
📚 Sources
- EloraTZP shows greater weight loss, A1C reduction than tirzepatide — Drug Topics, October 24, 2026
- Lilly's EloraTZP delivered greater weight loss and A1C reduction vs. tirzepatide 15 mg — Eli Lilly news release via PR Newswire, September 30, 2026
- Beyond GLP-1s: combination therapy, new hormones reshape obesity treatment — Yale Medicine, August 19, 2026