Key facts
- Eloralintide (LY3841136) is an investigational selective amylin receptor agonist from Eli Lilly, given as a once-weekly injection under the skin.[1]
- It is about 12 times more potent at the amylin 1 receptor than at the calcitonin receptor, which sets it apart from cagrilintide.[2]
- Its human half-life is 310 to 366 hours (about 13 to 15 days).[2]
- In a 48-week phase 2 trial of 263 adults, weight fell by up to 20.1% at 9 mg vs 0.4% on placebo.[1]
- It is not approved anywhere. Six ENLIGHTEN phase 3 trials are running, with first results expected from 2028.[6]
What Is Eloralintide?
Eloralintide is an investigational once-weekly amylin receptor agonist developed by Eli Lilly for obesity, tested in a 48-week phase 2 trial that reported up to 20.1% weight loss.[1]
Its development code is LY3841136. Chemically, it is a synthetic analogue of amylin, a 37-amino-acid hormone that the pancreas releases alongside insulin after meals. Lilly designed it to activate the amylin receptor while largely avoiding the calcitonin receptor, which earlier amylin analogues also stimulate.[2]
How Does Eloralintide Work?
Eloralintide works by activating amylin receptors, which Lilly says reduces calorie intake mainly by increasing the feeling of fullness after eating.[1]
Amylin receptors are formed when the calcitonin receptor pairs with a receptor activity-modifying protein (RAMP). Eloralintide is most active at AMY1R, the calcitonin receptor paired with RAMP1. In cell assays it was about 12-fold more potent at AMY1R (EC50 23.9 pM) than at the calcitonin receptor alone (291.0 pM), and about 11-fold more potent than at AMY3R (253.8 pM).[2]
Human receptors, cAMP assay. Source: Briere et al., Molecular Metabolism 2025.
In lean rats, eloralintide caused significantly less conditioned taste avoidance, a lab marker of nausea-like effects, than cagrilintide, which the authors describe as non-selective.[2]
Is Eloralintide a GLP-1?
No. Eloralintide does not act on the GLP-1 receptor; it is an amylin receptor agonist, a separate hormone pathway from GLP-1 drugs such as semaglutide and from GIP/GLP-1 drugs such as tirzepatide.
Because the pathways are different, Lilly is also testing eloralintide on top of tirzepatide. That combination, called EloraTZP, gave 23.3% weight loss at 48 weeks in people with type 2 diabetes, against 14.8% with tirzepatide 15 mg alone.[5] See eloralintide vs tirzepatide.
Eloralintide Structure and Half-Life
Eloralintide has a human half-life of 310 to 366 hours, roughly 13 to 15 days, which is why it can be dosed once a week.[2]
- It is an amylin analogue with a C20 fatty diacid attached at lysine 26 through a linker of two gamma-glutamic acid residues. The fatty acid binds albumin in the blood, which slows clearance.[2]
- Cysteines 2 and 7 are joined by a methylene thioacetal bond rather than the usual disulfide bridge.[2]
- The 12-week phase 1 study describes the half-life as about 2 weeks, with a steady-state peak-to-trough ratio of 1.28 to 1.38.[3]
- For comparison, the same discovery paper cites cagrilintide’s half-life as 159 to 195 hours.[2]
Eloralintide Trial Results at a Glance
In the 48-week phase 2 trial, mean weight loss ranged from 9.5% at 1 mg to 20.1% at 9 mg, against 0.4% with placebo.[1]
Efficacy estimand (as if everyone stayed on treatment), adults with obesity or overweight without type 2 diabetes, n = 263. Shown as weight lost. Source: Lilly, 6 Nov 2025; Billings et al., Lancet 2025.
Full breakdown, including phase 1 and the EloraTZP combination, in our eloralintide clinical trial results guide.
Who Makes Eloralintide?
Eli Lilly and Company discovered and develops eloralintide, the same company behind tirzepatide (Mounjaro, Zepbound) and retatrutide.[1]
Is Eloralintide Approved?
No. Eloralintide is investigational and not approved in any country; its ENLIGHTEN phase 3 trials have estimated primary completion dates from January to June 2028.[6]
Lilly has not published a filing date for eloralintide. Its retatrutide, by comparison, is planned for FDA submission in Q1 2027. Read more in eloralintide clinical trial results.
Frequently Asked Questions
What is eloralintide?
Eloralintide (LY3841136) is an investigational once-weekly selective amylin receptor agonist from Eli Lilly, being studied in phase 3 trials for obesity and overweight.
What is eloralintide used for?
It is being studied for the treatment of obesity and overweight, including in people with type 2 diabetes, sleep apnea and knee osteoarthritis. It is not approved for any use.
Is eloralintide a peptide?
Yes. It is a synthetic, lipidated peptide based on human amylin, with a fatty acid attached so it binds albumin and lasts about two weeks in the body.
What is the half-life of eloralintide?
About 310 to 366 hours (12.9 to 15.3 days) after single doses in healthy people, which supports once-weekly dosing.
Is eloralintide the same as cagrilintide?
No. Both are long-acting amylin analogues, but cagrilintide (Novo Nordisk) also strongly activates the calcitonin receptor, while eloralintide was designed to be selective for amylin receptors.
Sources
- Eli Lilly press release, 6 Nov 2025: eloralintide phase 2 results
- Briere DA, et al. Discovery and first-in-human study of eloralintide. Molecular Metabolism 2025;102:102271. DOI 10.1016/j.molmet.2025.102271
- Bhattachar S, et al. Eloralintide 12-week multiple-dose phase 1. Diabetes, Obesity and Metabolism 2026;28(4):2651-2660. DOI 10.1111/dom.70439
- Billings LK, et al. Eloralintide phase 2, 48-week trial. The Lancet 2025;406:2631-2643. DOI 10.1016/S0140-6736(25)02155-5
- Eli Lilly press release, 30 Sep 2026: EloraTZP (eloralintide + tirzepatide) phase 2b results
- ClinicalTrials.gov NCT07321886, ENLIGHTEN-1
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