Lilly Posts 23.3% Average Weight Loss For EloraTZP In Type 2 Diabetes, Setting Up Phase 3 Push

Eli Lilly reported that its amylin-Zepbound combination treatment eloraTZP produced 23.3% average weight loss at 48 weeks in adults with obesity or overweight and type 2 diabetes, a result the company presented as topping its own retatrutide in this harder-to-treat population. Lilly said it will use the readout to begin phase 3 trials in the fourth quarter of 2026.

The program combines eloralintide, an amylin receptor agonist, with Zepbound, Lilly’s approved GIP/GLP-1 medicine tirzepatide. In strategic terms, the update extends Lilly’s obesity franchise beyond single agents and toward combination regimens aimed at pushing efficacy higher in patients whose diabetes often dampens weight-loss responses.

The Data

The study, presented at the 62nd annual meeting of the European Association for the Study of Diabetes in Milan, Italy, compared several doses of eloraTZP, each component alone, and placebo in 367 adults with obesity or overweight and type 2 diabetes.

At the highest dose, Lilly said the combination yielded average weight loss of 54.1 pounds at 48 weeks and also showed A1C-lowering benefits. The company based the 23.3% average weight-loss figure on the efficacy estimand, defined as the efficacy had all randomized participants taken study treatment as directed for 48 weeks.

The strongest result came from patients who received eloralintide 9 mg plus Zepbound 15 mg. By comparison, eloralintide alone at 6 mg induced average weight loss of up to 28.6 pounds, Zepbound 15 mg alone led to an average loss of 34.4 pounds, and eloralintide 9 mg on its own produced average weight loss of 25.8 pounds.

Citi analysts wrote that the 23.3% average weight loss is both comparable to tirzepatide in patients without type 2 diabetes and notable because efficacy is typically attenuated in diabetes. They added that the result came in comfortably above their 17% weight-loss bar.

Safety And Development Risk

The main caveat in the update was tolerability. Adverse events were more frequent in the combination arm than with eloralintide or tirzepatide alone, and were mainly gastrointestinal. Treatment discontinuations were seen in up to 27% of patients treated with eloraTZP.

Citi said the discontinuations due to adverse events may reflect simultaneous initiation of both components, which could amplify tolerability challenges. The firm added that an optimized phase 3 titration approach could preserve efficacy while improving adherence.

That issue matters commercially as much as clinically. In obesity and diabetes, headline efficacy can win attention, but persistence on therapy affects real-world value. Lilly now has to show that the combination’s weight-loss advantage can be carried into phase 3 without unacceptable dropout levels.

The Competitive Picture

Lilly’s results arrived during a concentrated week of metabolic data. The company had already reported topline phase 3 retatrutide results in July, with fuller data presented this week showing that 34.9% of patients on retatrutide 12 mg lost at least 25% of body weight.

Elsewhere in amylin, Zealand Pharma reported primary endpoint data on its Roche-partnered amylin analog petrelintide showing 9.8% average weight loss at week 28. Novo is also pursuing the category by combining its amylin analog cagrilintide with semaglutide in CagriSema, though that program missed one endpoint in a phase 3 study in patients with type 2 diabetes in early August.

Lilly’s positioning is increasingly clear: rather than relying on one obesity mechanism, it is building multiple shots on goal across GIP, GLP-1 and amylin. If phase 3 confirms the efficacy and improves tolerability, eloraTZP could give the company another way to segment the market, especially in patients with obesity complicated by type 2 diabetes.