Eloralintide Guide

Eloralintide is Eli Lilly's long-acting, selective amylin receptor agonist — a once-weekly injection built to mimic amylin, the satiety hormone your pancreas releases alongside insulin every time you eat. It is investigational and not FDA-approved. If the mechanism sounds familiar, it should: eloralintide works the same satiety pathway as Novo Nordisk's cagrilintide, covered in our Cagrilintide guide. The difference is focus — cagrilintide is a DACRA, hitting amylin and calcitonin receptors together, while eloralintide is selective for the amylin receptor itself.

Amylin is not a minor hormone. It is one of the body's own meal-response signals, released with insulin in response to food. The incretin drugs that dominate this field — semaglutide, tirzepatide, retatrutide — all work the gut-hormone side of that response. None of them touches amylin. Eloralintide is Lilly building a drug for the signal the others left on the table.

Count the receptors. Semaglutide hits one (GLP-1). Tirzepatide hits two (GLP-1 + GIP). Retatrutide hits three (GLP-1 + GIP + glucagon) — and even the triple agonist, the most powerful single drug in the class, leaves the fourth pathway completely uncovered. That fourth pathway is amylin.

Why does the fourth pathway punch at the same weight as the other three? Because it speaks to a different part of the brain. GLP-1 drugs work largely through appetite circuits tied to the gut; amylin signals satiety through the hindbrain, a separate control center. Two independent "you are full" channels, not two volumes of the same channel. The trial data backs the claim: in the EloraTZP study, eloralintide alone produced up to 12.3% weight loss — the same neighborhood as tirzepatide alone (14.8%) in the very same trial. Amylin is not a supporting actor. It is a co-lead that nobody had cast.

Lilly paired eloralintide with tirzepatide — the combination it calls EloraTZP — in a phase 2b trial of 367 adults with obesity or overweight and type 2 diabetes, run in the US and Argentina over 48 weeks. The two drugs were given as separate once-weekly injections. Results were presented September 30, 2026, at the EASD meeting in Milan by investigator Liana K. Billings. Full coverage: our EloraTZP news article.

Body-weight change at 48 weeks. A1C fell up to 2.9 points on the top combination vs 2.4 on tirzepatide alone, from an average starting A1C of 8.1%.

The honest tension in the data is tolerability. Between 10.8% and 27% of participants on the combinations stopped treatment because of side effects — mostly gastrointestinal, concentrated in dose escalation — versus 2.9% on tirzepatide alone. More weight loss, more people stopping: bringing those discontinuation rates down with a slower, optimized escalation is the central job of the phase 3 program.

Here is the part of the story the press releases leave out. Years before EloraTZP read out, the research community had already worked out the same logic on its own: if the strongest drug in the field — retatrutide, three receptors — still leaves amylin uncovered, then pair it with the amylin drug that already exists. The result was the Reta + Cagri stack: retatrutide for GLP-1, GIP and glucagon, cagrilintide for amylin. All four pathways, covered. Lilly listened, ran the controlled version of the experiment with its own amylin agonist, and confirmed what biohackers had known for years.

The most common format is a pre-blended vial at a fixed 5:1 ratio — 12.5 mg retatrutide + 2.5 mg cagrilintide — though separate vials allow the staggered titration the protocol is known for: build retatrutide tolerance first, then layer cagrilintide in low. Both compounds are once-weekly, taken the same day at different injection sites. Protocol reference: Peptide Dosing Protocols — Cagrilintide + Retatrutide stack.

Headline results come from different trials and different populations — read across rows as a map of the field, not a head-to-head ranking. The one true head-to-head on this page is inside the EloraTZP trial itself, where every arm shared the same patients, protocol and 48 weeks. Note the pattern the table makes visible: the two single-pathway amylin drugs sit at the top of the combination story, because amylin is the one signal the incretin drugs cannot supply themselves.

Eloralintide is investigational and not FDA-approved. It is already in phase 3 development for obesity as a monotherapy. The EloraTZP trial dosed the two drugs as separate injections; the product Lilly intends to sell is a co-formulated single injection, with phase 3 studies of that co-formulation planned to begin by the end of 2026 on an optimized escalation schedule aimed squarely at the discontinuation problem.

The single-agonist era is ending. Semaglutide proved one pathway could change medicine; tirzepatide proved two were better; retatrutide is proving three. EloraTZP's lesson is that the fourth pathway was never inside those molecules at all — it was sitting in a different hormone, waiting for someone to add it. The community added it first. Now the largest drugmaker in the field is building its next flagship around the same idea.

• Eli Lilly and Company. Lilly's EloraTZP combination (eloralintide and tirzepatide) — investor news release, September 30, 2026.
• Peptopia Health. EloraTZP Beats Tirzepatide: 23.3% Weight Loss — Peptopia Smart Drug News, October 26, 2026.
• Peptopia Health. Cagrilintide Research Guide — mechanism, REDEFINE data, reconstitution and titration.
• Peptide Dosing Protocols. Cagrilintide + Retatrutide Stack Guide — pre-blend ratios and staggered titration protocol.
• Medical Xpress. New investigational drug delivers up to 23.3% weight loss in people with obesity and diabetes — EASD 2026 presentation coverage, September 2026.
• New Atlas. Mounjaro plus experimental drug dramatically boosts weight loss — EloraTZP phase 2b coverage, October 2026.