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eloraTZP: Lilly Is Stacking an Amylin on Top of Tirzepatide

Phase 1 data showed 17% weight loss at 16 weeks adding eloralintide to tirzepatide, versus 10% on tirzepatide alone. Phase 2 lands at EASD Milan this week.

Every obesity pipeline conversation in 2026 eventually arrives at the same question: what comes after the GLP-1s and the dual and triple agonists? Lilly’s answer this year has been amylin. And their newest play, eloraTZP, is not a new molecule at all - it is eloralintide, a selective amylin receptor agonist, layered directly on top of tirzepatide.

Phase 2 results are being unveiled at the EASD annual meeting in Milan this week, in an EASD-sponsored symposium on September 30. Here is the runway.

What the Research Says

The proof-of-concept numbers come from eloraTZP’s phase 1, which Lilly summarised in its September 15 EASD preview:

  • Adding eloralintide 3 mg to tirzepatide 5 mg produced 17% weight loss over 16 weeks, versus 10% on tirzepatide 5 mg alone, in adults with obesity or overweight
  • That is 7 percentage points of additional loss in a quarter of a year - a striking increment for a phase where tirzepatide doses are still climbing toward their full effect

The phase 2 program now extends that into adults with obesity or overweight and type 2 diabetes - the population that, as TRIUMPH-2 showed this week, tends to see blunted weight loss across every incretin. Results were submitted for presentation at EASD with full details due during the meeting.

Why the Amylin Stack Is the Interesting Bet

Amylin is the peptide hormone co-secreted with insulin that signals satiety through its own receptor pathway - separate from, and partly complementary to, GLP-1 and GIP signalling. Novo Nordisk has spent two years proving the concept with cagrilintide, first as a standalone and then fused with semaglutide as CagriSema. We covered that landscape in our CagriSema overview.

Lilly’s eloraTZP takes a different structural bet. Rather than building a single unimolecular dual agonist, it combines a selective amylin agonist with an existing approved-in-parts incretin. The design logic: keep each receptor’s pharmacology clean, tune the amylin dose independently, and avoid the compromises that come from engineering one peptide to hit multiple receptors at once. The trade-off is practical - it is two molecules in play, with the formulation and manufacturing complexity that implies.

There is also a strategic read. Eloralintide on its own has been advancing through Lilly’s pipeline as a potential standalone obesity agent, and Lilly is running amylin programs across multiple stages. If the combination works as the phase 1 suggested, the incremental-amylin-on-incretin approach becomes a platform: a next-generation add-on for patients who plateau on current therapy, which is most of them at some point.

What to Watch

Three things decide whether eloraTZP is a real contender or a science project:

  1. The diabetes population numbers. If the phase 2 shows the same relative increment in type 2 diabetes participants that the phase 1 showed in the general obesity cohort, that is the strongest possible signal, because every combo so far underperforms in that group
  2. Tolerability at the amylin dose. Amylin agonists add nausea and appetite suppression on top of an already nausea-heavy class. Where the GI curve lands determines usable doses
  3. Timelines. Nothing here is near a regulatory filing. EloraTZP is a phase 2 combination of two investigational molecules in most jurisdictions. This is 2028-and-beyond territory

The Australian Angle

Nothing in this pipeline has any Australian regulatory presence yet - eloralintide and the combination are not scheduled items because there is nothing to assess. The relevance for the Australian research interest community is directional: the next wave of obesity pharmacology is clearly amylin-centric, and both major players are converging on it from opposite structural directions. Watch the EASD readout to see whether the amylin-add-on thesis survives contact with the type 2 diabetes population.

For where the current approved landscape sits, see our tirzepatide page and semaglutide page, and our coverage of this week’s TRIUMPH-2 retatrutide readout.

Sources

Disclaimer: This article is for educational and informational purposes only. It does not constitute medical advice, therapeutic recommendations, or endorsements of any compound. Grey Highway is a research-education community. We do not sell, supply, or promote the use of research compounds. Always consult a qualified healthcare professional regarding health decisions. For Australian regulatory information, visit the TGA website.