Lilly Unveils Retatrutide and EloraTZP Data at EASD, Signaling Next-Gen Obesity Strategy

Key points

• Retatrutide phase 3 trial (Triumph-2) showed 20.8% average weight loss at 12 mg, with 34.9% of patients losing at least 25% of body weight.
• EloraTZP phase 2b trial demonstrated 23.3% average weight loss at the highest dose, outperforming tirzepatide alone (14.8%).
• Retatrutide reduced A1C by 1.4% to 1.6%, a smaller effect than tirzepatide, which lowered A1C by up to 2.4% in the EloraTZP trial.
• Lilly plans to file for FDA approval of retatrutide in the first quarter of 2027 and initiate phase 3 trials for EloraTZP by the end of 2026.
• EloraTZP showed higher discontinuation rates due to gastrointestinal side effects (10.8% to 27%) compared to tirzepatide alone (2.9%).

Background

Eli Lilly has previously reported topline data for retatrutide in July 2026, highlighting its potential as a next-generation obesity treatment. The company’s current market-leading drug, tirzepatide (sold as Mounjaro and Zepbound), targets two gut hormones, while retatrutide adds glucagon to the mix. This week’s announcements expand Lilly’s pipeline beyond single-molecule therapies to include combination approaches.

How outlets are covering it

Fierce Biotech emphasized retatrutide’s superior weight loss compared to tirzepatide but noted its modest impact on blood sugar control. CNBC focused on the EloraTZP combination, highlighting its potential to serve patients who do not respond to current GLP-1 drugs, while noting higher side effect rates. The Guardian described retatrutide as the 'Godzilla' of weight-loss drugs, stressing its broad cardiometabolic benefits but also detailing seven deaths in the trial, deemed unrelated to the drug. Eli Lilly’s official release presented EloraTZP as a 'physiological approach' targeting three nutrient-stimulated hormones, framing the higher discontinuation rates as manageable through dose adjustments in phase 3.

Why it matters

These results position Eli Lilly to maintain its dominance in the obesity and diabetes market by offering multiple next-generation options. Retatrutide’s approval could set a new benchmark for weight loss, while EloraTZP addresses unmet needs for patients who do not respond to current therapies. The data also intensifies competition with rivals like Novo Nordisk and Hengrui Pharma, which are developing similar multi-agonist treatments.

What to watch

Lilly will file for FDA approval of retatrutide in the first quarter of 2027 and initiate phase 3 trials for EloraTZP by the end of 2026. The company will also advance a co-formulation of EloraTZP to simplify administration. Rivals, including Hengrui Pharma and Kailera Therapeutics, are presenting early data on competing triple-agonist drugs, signaling a crowded future for obesity treatments.