EloraTZP Explained: Why Amylin + GIP/GLP-1 Is the Next Metabolic Research Frontier

Updated October 3, 2026. EloraTZP is an investigational combination being developed by Eli Lilly that pairs eloralintide, a selective amylin receptor agonist, with tirzepatide, a dual GIP/GLP-1 receptor agonist. New Phase 2b results presented at EASD 2026 have put the combination in focus as researchers explore whether targeting amylin and incretin pathways together can produce additional metabolic effects.

Important: EloraTZP is investigational. The results discussed here come from a Phase 2b clinical trial and do not establish regulatory approval, long-term safety, or superiority for routine clinical use.

What is EloraTZP?

EloraTZP combines two investigational/therapeutic mechanisms: eloralintide targets the amylin pathway, while tirzepatide activates GIP and GLP-1 receptors. Lilly describes the combination as a triple-acting investigational approach spanning amylin, GIP and GLP-1 signaling.

Amylin is released after eating and contributes to satiety. Eloralintide is designed to preferentially activate the AMY1 receptor. Tirzepatide, meanwhile, targets GIP and GLP-1 receptors involved in appetite and glucose regulation. The scientific question is whether combining these pathways can extend metabolic effects beyond either component alone.

What did the Phase 2b EloraTZP trial find?

The 48-week Phase 2b study enrolled 367 adults in the United States and Argentina who had obesity or overweight and type 2 diabetes. Participants were randomized to placebo, eloralintide, tirzepatide, or different EloraTZP dose combinations.

According to Lilly’s September 30, 2026 results, the highest reported EloraTZP combination produced an average body-weight reduction of 23.3%, or 54.1 lb, compared with 14.8%, or 34.4 lb, with tirzepatide 15 mg. Average A1C reduction reached up to 2.9 percentage points with EloraTZP versus 2.4 percentage points with tirzepatide 15 mg.

Why the amylin + GIP/GLP-1 combination matters

Much of the recent obesity-drug landscape has centered on incretin biology. EloraTZP adds a distinct satiety pathway through selective amylin receptor agonism. That makes the program scientifically important even before Phase 3: it tests whether complementary nutrient-responsive pathways can be combined to influence appetite, body weight and glycemic control.

What are the main limitations?

These are Phase 2b results, not final Phase 3 evidence. The trial population consisted specifically of adults with obesity or overweight and type 2 diabetes, so the findings should not automatically be generalized to other populations. Lilly sponsored the study, and the announced results require interpretation alongside the complete trial data.

Tolerability is also important. Lilly reported that gastrointestinal adverse events were the most common and were generally mild or moderate, occurring mainly during dose escalation. Discontinuation due to adverse events ranged from 10.8% to 27.0% across EloraTZP groups, compared with 2.9% for tirzepatide in the study. Dose-escalation strategy will therefore be an important issue to watch in later trials.

Is EloraTZP approved?

No. EloraTZP remains investigational. Lilly has said it plans to advance a co-formulated EloraTZP product into Phase 3 development in the fourth quarter of 2026. Successful Phase 2 results do not guarantee Phase 3 success or regulatory approval.

EloraTZP vs retatrutide: are they the same?

No. The mechanisms are different. EloraTZP combines selective amylin receptor agonism with tirzepatide’s GIP/GLP-1 activity. Retatrutide is a single investigational molecule designed to activate GIP, GLP-1 and glucagon receptors. Results from separate trials should not be used to declare one approach superior because study populations, durations, doses and statistical methods differ.

What happens next?

The next major milestone is Phase 3. Researchers will be watching whether the magnitude of weight and A1C changes persists in larger and longer trials, whether revised dose escalation improves tolerability, and how the combination performs across populations with and without type 2 diabetes.

Frequently asked questions

What does EloraTZP contain?

EloraTZP combines eloralintide, an investigational selective amylin receptor agonist, with tirzepatide, a dual GIP/GLP-1 receptor agonist.

How much weight was lost in the Phase 2b trial?

Lilly reported average weight loss of up to 23.3% at 48 weeks with the highest reported combination, compared with 14.8% with tirzepatide 15 mg in this study.

Is EloraTZP in Phase 3?

The reported study was Phase 2b. Lilly says it plans to initiate Phase 3 development of a co-formulation in Q4 2026.

Is EloraTZP approved in Canada or the United States?

No. EloraTZP is investigational and the Phase 2b findings should not be interpreted as regulatory approval.

Sources

Eli Lilly and Company: Phase 2b EloraTZP results, September 30, 2026.

Eli Lilly and Company: What to know about eloralintide and EloraTZP.