Lilly's new weight loss combo drug outperforms tirzepatide in latest trial

Eli Lilly reported positive results from a study following EloraTZP, its experimental combination weight loss drug. Patients on the highest dose lost an average of 23.3% of their body weight, compared to 14.8% for those on tirzepatide alone (1).

• Eli Lilly (LLY) issued a news release on September 30, 2026, to announce positive trial results for EloraTZP, its experimental weight loss drug.
• EloraTZP is a combination of two drugs: eloralintide, an amylin receptor agonist, and tirzepatide, a GIP/GLP-1 receptor agonist. Together, the drugs target three hormonal pathways that help regulate blood sugar and appetite.
• The 48-week study followed 367 patients who were obese or overweight and had type 2 diabetes. It compared EloraTZP to eloralintide alone, tirzepatide alone, and a placebo.
• Participants on the highest-tested combination dose of EloraTZP lost an average of 54.1 pounds, or 23.3% of their body weight, compared to 34.4 pounds, or 14.8% of body weight, for those taking 15mg of tirzepatide alone.
• EloraTZP also reduced A1C by up to 2.9 percentage points, compared to a 2.4-point reduction for tirzepatide alone.
• The reported side effects were generally mild or moderate, with gastrointestinal issues being the most common, though they occurred more often for those taking the combination drug. The rate of discontinuation due to side effects ranged from 10.8% to 27.0% for those taking EloraTZP.
• The next phase of studying the drug, using a more optimized dose-escalation schedule, is slated to begin by the end of this year.
• Reuters reports that Novo (NVO) is on track to launch the first combination obesity drug, CagriSema, early next year. Though also a combination drug, CagriSema relies on different medications — cagrilintide and semaglutide (2, 3).
• In an interview with CNBC, Ken Custer, president of Lilly Cardiometabolic Health, said drugs like tirzepatide or eloralintide on their own may not give patients what they need. But when combined together, they can offer more weight loss benefits. He said the combo drug may “turn out to be a really winning approach” (4).

Sources & Further Reading

1. "Lilly's EloraTZP (combination of eloralintide and tirzepatide) delivered greater weight loss and A1C reduction vs. tirzepatide 15 mg in adults with obesity and type 2 diabetes." Eli Lilly and Company. September 30, 2026.
2. "Experimental Lilly combination drug tops Zepbound in weight-loss trial." Reuters. September 30, 2026.
3. "Novo Nordisk A/S: CagriSema demonstrated superior HbA1c reduction of 1.91%-points and weight loss of 14.2% in adults with type 2 diabetes in the REIMAGINE 2 trial." Novo Nordisk. February 2, 2026.
4. "Eli Lilly says closely watched combo obesity regimen boosts weight loss in mid-stage trial." CNBC. September 30, 2026.