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Eloralintide

Gray market

Checked · 17 sources · 6 corrections on this page · No vendors · No affiliates · No one buys a word of it

−20% body weight

Phase II · 48 weeks · on 9 mg · a Phase 2 trial of 263 adults · Billings 2025

Gray market · No FDA ruling — not on any list

Not sold: trial drug only.

Bottom line

A strong Phase 2 result from one company’s trials; Phase 3 will show whether it holds.

Also called
  • LY3841136
  • once-weekly selective amylin receptor agonist
  • fatty-acid-acylated amylin analog
  • Eli Lilly and Company
Category
Peptide — Selective Amylin Receptor Agonist
Class
Selective amylin receptor (AMY1R) agonist
Engineering
Amylin analog acylated with C20 fatty diacid
Half-life
Once-weekly SubQ
Route (studied)
SubQ (people)
Route (sold)
Not sold: trials only
FDA Status
Investigational — Phase 3 enrollment initiated late 2025
Pipeline
  • Phase 3 ENLIGHTEN-1 (obesity) (NCT07321886), primary completion est. Mar 2028
  • Phase 3 ENLIGHTEN-2 (obesity with type 2 diabetes) (NCT07282600), primary completion est. Jan 2028
Phase 2 Weight Loss
Up to ~20% at 48 weeks (9 mg)
Receptor Selectivity
AMY1R 12× over CTR
Pivotal Phase 2
NCT06230523 (Lancet 2025)
Developer
Eli Lilly and Company
Cost & Access
Research-only (investigational)

Also for weight loss

The other four questions

What does it do? In rats it cut food intake and body weight, mostly fat (Briere et al., 2025). It acts on amylin receptors, preferring the amylin 1 receptor, and not on GLP-1 receptors (Briere et al., 2025).
Who uses it? Trial participants: it is investigational, with no approved product.
Does the evidence hold up? In a 48-week Phase 2 trial in 263 adults, weight fell 20% on 9 mg against 0.4% on placebo (Billings et al., 2025); in the 12-week Phase 1, weight fell 2.6% to 11.3% across doses (Bhattachar et al., 2026). Lilly said Phase 3 would start by the end of 2025 (Lilly, November 6, 2025).
Bottom line? A strong Phase 2 result from one company’s trials; Phase 3 will show whether it holds.

Dosing from the Literature

Published for fat loss: trial doses, single shots up to 12 mg and weekly doses up to 9 mg in Phase 2. Not published: an approved dose; Phase 3 started in late 2025.

The rows give the doses tested in the Phase 1 and Phase 2 trials, with who received them. No approved dose exists.

Dose / ScheduleSourceOutcomeNotes
0.04–12 mg single dosePhase 1 (NCT05295940; Briere et al., 2025)Weight −2.5% at 4 mg and −4.4% at 12 mg by week 4, vs +0.6% on placebo48 healthy participants; 16 mostly mild adverse events in nine people on eloralintide.
Five ascending weekly doses, 12 weeksPhase 1 (Bhattachar et al., 2026)Weight −2.6% to −11.3% across dose groups100 adults with obesity or overweight; decreased appetite 19%, diarrhoea 10%, nausea 8%, vomiting 4%.
1 mg weekly × 48 weeksPhase 2 (NCT06230523; Billings et al., 2025)−9% weightNausea 11%, fatigue 0%.
3 mg weekly × 48 weeksPhase 2 (Billings et al., 2025)−12% weightNausea 13%, fatigue 13%.
6 mg weekly × 48 weeksPhase 2 (Billings et al., 2025)−18% weightNausea 64%, fatigue 29%.
9 mg weekly × 48 weeksPhase 2 (Billings et al., 2025)−20% weightNausea 33%, fatigue 43%.
6→9 mg escalationPhase 2 (Billings et al., 2025)−20% weightNausea 54%, fatigue 46%.
3→9 mg escalationPhase 2 (Billings et al., 2025)−16% weightNausea 25%, fatigue 21%. All Phase 2 arms: 263 adults with obesity or overweight and a weight-related condition, without type 2 diabetes; placebo −0.4%, nausea 14%, fatigue 12%.
Dosing Disclaimer

Eloralintide is investigational, and no approved dose exists; the rows are trial doses. Consult a licensed healthcare provider.

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What It Is

Eloralintide (development code LY3841136) is an investigational once-weekly subcutaneous amylin receptor agonist being developed by Eli Lilly and Company for chronic weight management. Chemically, it is a synthetic analog of human amylin — the 37-amino-acid peptide hormone co-secreted with insulin from pancreatic beta cells in response to nutrient intake — conjugated at lysine 26 to a C20 fatty diacid that binds serum albumin to extend its half-life for once-weekly dosing (Briere et al., 2025). The engineering objective was a long-acting amylin analog with sufficient receptor selectivity to drive the satiety and body-weight effects of the amylin pathway while limiting the receptor cross-reactivity that contributes to gastrointestinal tolerability burden in non-selective agonists (notably cagrilintide).

Endogenous amylin, together with insulin, regulates postprandial glucose via three established mechanisms: slowing gastric emptying, suppressing postprandial glucagon secretion, and promoting satiety through central receptors in the area postrema and hypothalamus. Native amylin has a plasma half-life of approximately 10 minutes, making it impractical as a therapeutic. Pramlintide (Symlin®), the first amylin analog in clinical use, addressed the aggregation problem of native amylin but retained the short half-life and requires 3× daily injection at mealtime. Cagrilintide (Novo Nordisk) extended amylin therapy to once-weekly dosing using a C20 fatty diacid conjugation strategy similar to eloralintide's, and is currently paired with semaglutide as CagriSema in Phase 3 trials. Eloralintide is Lilly's answer to Novo's CagriSema — a long-acting amylin analog intended to be paired with tirzepatide in the most important head-to-head combination in the 2026 obesity pipeline.

The key differentiator Lilly emphasizes is receptor selectivity. Amylin acts at a family of related receptors formed by the calcitonin receptor (CTR) complexed with receptor activity-modifying proteins (RAMPs): AMY1R (CTR + RAMP1), AMY2R (CTR + RAMP2), and AMY3R (CTR + RAMP3), plus CTR alone. Different amylin analogs engage these receptors with different selectivity profiles, and the weight-loss and GI-tolerability effects are thought to be differentially distributed across AMY1R vs CTR / AMY3R engagement. Eloralintide was engineered to activate AMY1R approximately 12-times more potently than CTR, with reduced AMY3R activity (Briere et al., ScienceDirect 2025). This selectivity is Lilly's central commercial thesis: strong efficacy through AMY1R-mediated satiety with reduced nausea and fatigue through avoidance of broader CTR/AMY3R activation.

As of April 2026, eloralintide has completed Phase 1 and Phase 2 monotherapy trials in obesity, has additional Phase 2 programs testing combination with tirzepatide in T2D-plus-obesity populations (NCT06603571) and in monotherapy in obesity without diabetes (NCT06297616, NCT06916091), and began Phase 3 enrollment at the end of 2025 per Lilly's November 2025 Phase 2 topline announcement. It has no approval anywhere.

Mechanism of Action

Eloralintide is a long-acting amylin analog with a measured preference among the amylin receptors (Briere et al., 2025).

  • Selective AMY1R activation — In cells expressing the human receptors, eloralintide activated the amylin 1 receptor (AMY1R, the calcitonin receptor with RAMP1) 12 times more potently than the calcitonin receptor and 11 times more than AMY3R; in rats, AMY1R and AMY3R were both activated more potently than the calcitonin receptor (Briere et al., 2025).
  • Food intake and weight in rats — In diet-induced obese rats it lowered food intake and body weight, mostly through fat loss, and caused less conditioned taste avoidance than cagrilintide (Briere et al., 2025).
  • Amylin’s known actions — Reviews describe amylin ending meals through the brainstem’s area postrema, and amylin agonists lowering eating and body weight in animal and human studies (Lutz, 2010; Boyle et al., 2018).
  • C20 fatty diacid acylation for albumin binding — A C20 fatty diacid attached at lysine 26 binds serum albumin, extending its half-life for once-weekly dosing (Briere et al., 2025).
  • What it does not do — It was designed and tested as an amylin receptor agonist; the published assays tested amylin and calcitonin receptors, not GLP-1 or GIP receptors (Briere et al., 2025).
  • Receptor biology caveats — The AMY1R selectivity is Lilly’s framing of its own data; whether it explains the tolerability seen so far has not been tested in people.

What the Research Shows

Eloralintide’s evidence comes from Lilly’s own studies: cell and animal work, two Phase 1 trials, and a 48-week Phase 2 trial in 263 adults published in The Lancet in 2025 (Briere et al., 2025; Bhattachar et al., 2026; Billings et al., 2025).

  • Preclinical — discovery through clinical proof of concept (Briere et al., Mol Metab 2025) — Full translational characterization of eloralintide. In vitro: AMY1R selectivity ~12× over CTR. In rats and monkeys: favorable pharmacokinetics. In diet-induced obese rats: dose-dependent reduction of food intake and body weight, primarily through fat mass loss. Conditioned-taste-avoidance comparison: significantly less taste avoidance than cagrilintide at matched weight-loss doses (supporting the improved GI tolerability hypothesis).
  • Phase 1 single-ascending dose (NCT05295940 Part A) — Evaluated doses of 0.04 to 12 mg in healthy participants. Safety and pharmacokinetic proof of concept. Plasma exposure dose-proportional at PK-relevant ranges.
  • Phase 1 multiple-ascending dose (Bhattachar et al., Diabetes Obes Metab 2026; PMID 41559929) — 100 participants over 12 weeks, five multiple-ascending dose cohorts. Once-weekly dosing produced up to approximately 11% bodyweight reduction after 12 weeks. Most common treatment-emergent adverse events were decreased appetite (19%), headache (12%), fatigue (11%), and COVID-19 (11%). Notably low GI adverse-event rate by amylin-class standards.
  • Phase 2 pivotal trial (NCT06230523; Billings et al., Lancet 2025) — 48-week, multicenter, double-blind, randomized, placebo-controlled trial in 263 adults with obesity or overweight plus at least one weight-related comorbidity and without type 2 diabetes. Mean baseline characteristics: age 49.0 years, bodyweight 109.1 kg, BMI 39.1 kg/m², 78% female, 78% White. Randomization included fixed doses (1, 3, 6, 9 mg weekly) and two escalation arms (6–9 mg and 3–9 mg), plus placebo.
  • Phase 2 efficacy — Mean percent change in bodyweight at 48 weeks: 1 mg −9% (95% CI −12.6 to −6.3); 3 mg −12% (−14.9 to −9.8); 6 mg −18% (−20.7 to −14.5); 9 mg −20% (−22.7 to −17.5); 6–9 mg escalation −20%; 3–9 mg escalation −16%; placebo −0.4%. Clear dose-response. The 9 mg dose's approximately 20% weight reduction at 48 weeks is competitive with tirzepatide's approximately 20% at 72 weeks (SURMOUNT-1) and exceeds semaglutide 2.4 mg's approximately 15% at 68 weeks (STEP-1).
  • Phase 2 tolerability — Most common adverse events were nausea (placebo 14%; 1 mg 11%; 3 mg 13%; 6 mg 64%; 9 mg 33%; 6–9 mg 54%; 3–9 mg 25%) and fatigue (placebo 12%; 1 mg 0%; 3 mg 13%; 6 mg 29%; 9 mg 43%; 6–9 mg 46%; 3–9 mg 21%). The 6 mg arm's high nausea rate is notable; the slower 3–9 mg escalation arm showed substantially lower nausea (25%) with meaningful 16% weight loss — the titration design appears tolerability-critical and is likely the Phase 3 template.
  • Combination with tirzepatide — completed (NCT06603571) — Phase 2 study of eloralintide alone or with tirzepatide in 367 adults with obesity or overweight and T2D, completed September 14, 2026; Lilly presented results at EASD on September 30, 2026 (see the Tirzepatide card under Commonly Stacked With), and no journal has published them yet. The combination is the probable commercial vehicle for eloralintide in the obesity market if the monotherapy Phase 3 supports approval.
  • Additional Phase 2 monotherapy programs (NCT06297616, NCT06916091) — Additional Phase 2 work expanding the monotherapy database ahead of Phase 3 enrollment.
  • Phase 3 initiated — Lilly announced November 6, 2025 that Phase 3 enrollment in obesity monotherapy would begin by year-end 2025 based on the Phase 2 Lancet result.
Research Context — A Strong Phase 2, Not Yet a Phase 3

Eloralintide's Phase 2 weight-loss result (up to 20% at 48 weeks) is one of the most compelling amylin-class data sets published to date. The improved GI tolerability relative to cagrilintide — if it holds — is a clinically meaningful differentiation. But a single Phase 2 is not a Phase 3; enrollment size, trial duration, and broader patient population in Phase 3 can change the safety and efficacy picture. The 6 mg fixed-dose nausea rate (64%) also illustrates that eloralintide is not a nausea-free drug — titration matters.

Human Data

All currently published eloralintide human data comes from Lilly's clinical-trial program. There is no off-label or gray-market human experience.

  • NCT05295940 — Phase 1 single- and multiple-ascending dose — Safety, PK, and weight-loss proof of concept in healthy participants and adults with obesity. Up to ~11% bodyweight reduction at 12 weeks in the MAD portion. Favorable GI tolerability relative to amylin-class expectations.
  • NCT06230523 — Phase 2 monotherapy obesity (Billings et al., Lancet 2025) — 263 adults, 48 weeks, dose-response and titration-design evaluation. Pivotal efficacy and tolerability data summarized above.
  • NCT06297616 — Phase 2 monotherapy extension — Additional Phase 2 data in obesity monotherapy. Specific endpoints and topline status per Lilly's pipeline reporting.
  • NCT06916091 — Phase 2 monotherapy study — Additional Phase 2 program expanding the dataset.
  • NCT06603571 — Phase 2 eloralintide ± tirzepatide in T2D + obesity — The combination program. Topline expected to influence Phase 3 design for both monotherapy and combination arms.
  • NCT06345066, NCT06916065 — additional tirzepatide-combination programs — Extended Phase 2 evaluation of the combination in different populations.
  • Phase 3 enrollment initiated end of 2025 — ClinicalTrials.gov registry expected to add Phase 3 monotherapy and combination protocols in early 2026.
  • No off-trial human use — Eloralintide is not commercially available, not compounded, not sold through research-chemical channels.

Reconstitution & Storage

No published source describes how eloralintide is supplied, mixed or stored outside its trials; in the trials it was a once-weekly injection under the skin (Billings et al., 2025; Bhattachar et al., 2026).

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Side Effects & Risks

Important

Eloralintide is investigational and not FDA-approved. In its trials nausea and fatigue were the most common side effects (Billings et al., 2025). With tirzepatide, in Lilly’s Phase 2 trial, stomach side effects were more frequent on the pairs and 10.8% to 27.0% stopped for side effects (company results, September 30, 2026). Consult a licensed healthcare provider.

In the 48-week Phase 2 trial, nausea and fatigue were the most common adverse events, and both rose with dose (Billings et al., 2025).

  • Nausea — 11% at 1 mg, 13% at 3 mg, 64% at 6 mg, 33% at 9 mg, 54% with 6→9 mg escalation and 25% with 3→9 mg escalation, against 14% on placebo; the 3→9 mg arm lost 16% of body weight, against 20% on 9 mg (Billings et al., 2025).
  • Fatigue — 0% at 1 mg, 13% at 3 mg, 29% at 6 mg, 43% at 9 mg, 46% with 6→9 mg and 21% with 3→9 mg, against 12% on placebo (Billings et al., 2025).
  • Diarrhoea, vomiting — Infrequent in the 12-week Phase 1: diarrhoea 10%, nausea 8%, vomiting 4% (Bhattachar et al., 2026).
  • Decreased appetite — The most common adverse event in the Phase 1, in 19% (Bhattachar et al., 2026).
  • Serious adverse events — One in the Phase 1, judged unrelated to eloralintide; no deaths (Bhattachar et al., 2026).

Bloodwork & Monitoring

No label or guideline sets monitoring for eloralintide. The trials measured body weight, safety and tolerability, and blood levels of the drug (Billings et al., 2025; Bhattachar et al., 2026).

Commonly Stacked With

Tirzepatide (Lilly-developed combination)

Lilly tests the two together, as separate injections, under the name EloraTZP. In its Phase 2 trial NCT06603571 (367 adults with type 2 diabetes and obesity or overweight, 48 weeks), Lilly reported 23.3% weight loss on eloralintide 9 mg with tirzepatide 15 mg vs 14.8% on tirzepatide 15 mg alone, had everyone stayed on treatment. Stomach side effects were more frequent on the pairs, and 10.8% to 27.0% stopped for side effects on the pairs vs 2.9% on tirzepatide alone and 16.7% on placebo (EASD, September 30, 2026). No journal has published the trial yet (checked October 3, 2026).

Tested together in people: none published · a Phase 2 trial’s results were presented at EASD on September 30, 2026; no journal yet · Read the receipt →

Retatrutide (Lilly's tri-agonist)

Lilly’s GLP-1, GIP and glucagon tri-agonist, in Phase 3. No study has tested the two together, and ClinicalTrials.gov lists no trial of the pair (October 3, 2026).

Tested together in people: none published · Read the receipt →

Stacking this? Read the receipt →

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Legal Status

Current Status — April 2026

Eloralintide is investigational. It has no FDA, EMA, or other major-regulator approval. The compound has completed Phase 1 and the pivotal 48-week Phase 2 monotherapy obesity trial (NCT06230523; Billings et al., Lancet 2025). Lilly announced November 6, 2025 that Phase 3 enrollment in obesity monotherapy would begin by year-end 2025. Phase 2 combination work with tirzepatide (NCT06603571) is ongoing.

Eloralintide is not on the FDA Category 2 Bulk Drug Substances list and was not among the 12 peptides FDA removed from it in April 2026 (FDA 503A categories list, April 22, 2026). As an investigational NDA-track biologic developed by Eli Lilly, it exists entirely within the conventional pharmaceutical regulatory framework.

WADA: Not specifically named on the WADA Prohibited List as of the 2026 edition. The List does not name amylin-class compounds. This is hypothetical for eloralintide in 2026 given the lack of availability outside trials.

Cost & Access

Eloralintide is given only within Lilly-sponsored clinical trials. It is not on FDA’s compounding lists, and no approved product exists.

Estimated pricing as of April 2026. Actual costs vary by provider, location, and prescription status. Kalios does not sell compounds.

References

  1. Billings LK, Hsia S, Bays H, Tidemann-Miller B, O'Hagan J, Tham LS, et al. Eloralintide, a selective amylin receptor agonist for the treatment of obesity: a 48-week phase 2, multicentre, double-blind, randomised, placebo-controlled trial. Lancet. 2025;406(10520):2631-2643. PMID: 41207310. (NCT06230523 — pivotal Phase 2; up to 20% weight loss at 9 mg over 48 weeks.)
  2. Bhattachar S, Tham LS, Tidemann-Miller B, et al. Eloralintide, a selective, long-acting amylin receptor agonist for treatment of obesity: Phase 1 proof of concept. Diabetes Obes Metab. 2026;28(4):2651-2660. PMID: 41559929. (Phase 1 multiple-ascending-dose results; 100 participants, up to ~11% weight loss at 12 weeks.)
  3. Briere DA, Qu H, Lansu K, He MM, Moyers JS, Coskun T, et al. Eloralintide (LY3841136), a novel amylin receptor agonist for the treatment of obesity: From discovery to clinical proof of concept. Mol Metab. 2025;102:102271. PMID: 41109426. (Full translational characterization; AMY1R selectivity, preclinical weight loss, conditioned-taste-avoidance comparison vs cagrilintide.)
  4. Briere DA, Long A, Bullock DM, et al. 849-P: Eloralintide (LY3841136), a Selective Amylin Mimetic, Lowered Body Weight with Improved Quality of Weight Loss and GI Tolerability in Rats Compared with Cagrilintide. Diabetes 2025;74(Suppl 1):849-P. DOI: 10.2337/db25-849-p. (ADA 2025 scientific sessions preclinical comparison.)
  5. Eli Lilly and Company. Lilly's selective amylin agonist, eloralintide, demonstrated meaningful weight loss and favorable tolerability in a Phase 2 study of adults with obesity or overweight. Press release, November 6, 2025. (Phase 2 topline announcement; Phase 3 enrollment initiation.)
  6. ClinicalTrials.gov NCT05295940 — A Study of LY3841136 in Healthy Participants. (Phase 1 SAD/MAD.)
  7. ClinicalTrials.gov NCT06230523 — A Study of LY3841136 in Adult Participants With Obesity or Overweight. (Pivotal Phase 2.)
  8. ClinicalTrials.gov NCT06603571 — A Study to Investigate Weight Management With LY3841136 and Tirzepatide (LY3298176), Alone or in Combination, in Adult Participants With Obesity or Overweight With Type 2 Diabetes. (Combination Phase 2.)
  9. ClinicalTrials.gov NCT06297616, NCT06916091 — Additional Phase 2 eloralintide monotherapy programs.
  10. Lutz TA. The role of amylin in the control of energy homeostasis. Am J Physiol Regul Integr Comp Physiol. 2010;298(6):R1475-R1484. PMID: 20357016.
  11. Hay DL, Chen S, Lutz TA, Parkes DG, Roth JD. Amylin: Pharmacology, Physiology, and Clinical Potential. Pharmacol Rev. 2015;67(3):564-600. PMID: 26071095.
  12. Boyle CN, Lutz TA, Le Foll C. Amylin — Its role in the homeostatic and hedonic control of eating and recent developments of amylin analogs to treat obesity. Mol Metab. 2018;8:203-210. PMID: 29203236.
  13. Amylin: emergent therapeutic opportunities in overweight, obesity and diabetes mellitus. Nat Rev Endocrinol. 2025;21:482-494. PMID: 40360789. (Modern review of the amylin drug class including eloralintide context.)
  14. Lau DCW, Erichsen L, Francisco AM, et al. Once-weekly cagrilintide for weight management in people with overweight and obesity: a multicentre, randomised, double-blind, placebo-controlled and active-controlled, dose-finding phase 2 trial. Lancet. 2021;398(10317):2160-2172. PMID: 34798060. (Cagrilintide Phase 2 — the class comparator.)
  15. Frias JP, Deenadayalan S, Erichsen L, et al. Efficacy and safety of co-administered once-weekly cagrilintide 2.4 mg with once-weekly semaglutide 2.4 mg in type 2 diabetes: a multicentre, randomised, double-blind, active-controlled, phase 2 trial. Lancet. 2023;402(10403):720-730. PMID: 37364590. (CagriSema Phase 2 — the combination benchmark.)
  16. Garvey WT, Ard J, Connery L, et al. Petrelintide, a human amylin analogue for the treatment of obesity (ZUPREME 1): a randomised, double-blind, placebo-controlled, phase 2 trial. Lancet Diabetes Endocrinol. 2026. doi:10.1016/S2213-8587(26)00213-5. PMID: 42810355. (The class comparator's published Phase 2.)
  17. FDA. Bulk Drug Substances Nominated for Use in Compounding Under Section 503A of the FD&C Act (503A categories list), versions updated April 15, April 22 and May 14, 2026. fda.gov/media/94155/download. Read October 3, 2026. (Notice that 12 peptides would leave Category 2 because their nominations were withdrawn; their removal; GHK-Cu, except injectable, back in Category 1.)

Also for weight loss

Tested together in people

None published · Read the receipt →

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Checked 13 Oct 2026