Last Tuesday in Milan, Eli Lilly did something the obesity drug field has not seen before. Participants taking EloraTZP lost up to an average of 54.1 lbs (23.3%) and lowered their A1C by up to an average of 2.9% at 48 weeks, beyond what either medicine achieved alone. That number, presented at the EASD annual meeting on September 30, is the highest Phase 2 weight-loss figure the category has produced. Participants receiving the highest-dose combination lost 23.3% of body weight, compared with 14.8% among those receiving tirzepatide 15 mg alone and 11.1% in those receiving eloralintide 9 mg alone.
Eloralintide is a selective amylin receptor agonist, and tirzepatide is a dual GIP/GLP-1 receptor agonist. Stacking a third mechanism on top of Zepbound is the architectural logic here. The pancreatic hormone amylin works alongside insulin to signal fullness and slow stomach emptying, offering a separate biological mechanism from GLP-1 receptor agonists. The combination effectively recruits three distinct metabolic pathways at once. Lilly plans to advance an EloraTZP co-formulation product into Phase 3 by the end of 2026.
The Bull Case: A Commanding Lead
For LLY bulls, the Milan data did more than move a number. They redefined the competitive ceiling. Type 2 diabetes patients are notoriously harder to treat for weight, which makes the 23.3% figure more striking, not less.
EloraTZP addresses the pool of patients who have tried GLP-1s and struggled with efficacy or tolerability directly. Beyond the combination therapy, Lilly is positioning eloralintide as part of a broader future franchise tied to Zepbound and Mounjaro. That means standalone eloralintide, combination EloraTZP, and the existing blockbusters all reinforcing one another commercially. Competitors trying to answer 23.3% from Phase 2 will need years just to get to the same table.
The Bear Case: Novo Has Product, Lilly Has a Promise
The Milan number is real. The drug is not yet. EloraTZP in Phase 3 co-formulation will take at least two to three years to reach approval, and the field’s history of Phase 2 enthusiasm fading in larger trials is long. The more immediate problem for the bull case is tolerability. More patients taking both drugs, 10.8% to 27% depending on the dose, discontinued treatment due to side effects, compared with 2.9% of people on tirzepatide alone in the trial.
Meanwhile, Novo Nordisk (NVO) is considerably further along than the current news cycle implies. Novo filed a New Drug Application for CagriSema, its once-weekly obesity combination, on December 18, 2025, and Novo has said an FDA decision is expected in Q4 2026. When assessing the treatment effect assuming all patients remained on therapy, mean weight loss reached 22.7% with CagriSema versus 2.3% with placebo. That is within rounding distance of EloraTZP’s headline, and CagriSema is months from potential approval, not years from Phase 3. Reuters reported in September 2026 that Novo outlined a multi-year rollout targeting standalone cagrilintide and a higher-dose version of CagriSema in 2028, among other new obesity products. Novo is also advancing amycretin, a potential oral GLP-1/amylin approach that could be among the most commercially valuable drug formats in the obesity space.
On pricing power, Novo retains real leverage. Wegovy’s commercial infrastructure is established globally. CagriSema slots into that infrastructure. A Lilly co-formulation entering a market where Novo already holds formulary position will face a harder commercial climb than the clinical numbers suggest.
Where the Evidence Leads
The Milan data belong to Lilly. A 23.3% result in a diabetic population, with A1C down up to 2.9 points, is a genuine scientific achievement and meaningfully extends what the category thought was possible. The discontinuation data temper the excitement, but Lilly has time to address tolerability in Phase 3 design.
The bear case for Lilly is not that EloraTZP fails. It is that the obesity race has more than one finish line. Novo’s CagriSema should receive an FDA decision this quarter. Viking Therapeutics (VKTX), with VK2735 in Phase 3 VANQUISH trials fully enrolled, showed approximately 22% weight loss by Week 33 in an exploratory weekly-dosing cohort in a maintenance study, with every-other-week dosing maintaining up to 97% of prior weight loss. The field is not waiting for Lilly’s Phase 3.
The verdict: the Milan data reinforce Lilly’s position as the innovation leader in obesity pharmacology. But declaring the race over confuses the best clinical number with the best commercial position. Novo holds the near-term market catalyst. Lilly holds the longer-term scientific high ground. Both are worth owning with different time horizons. The stock that deserves the most scrutiny after Milan is NVO: if CagriSema launches into a market where physicians have already seen 23.3%, the pricing and differentiation conversation gets harder, not easier.
