Eloralintide

Eloralintide (LY3841136) is an investigational, selective, long-acting amylin receptor agonist under development by Eli Lilly for chronic weight management. Amylin is a hormone co-secreted with insulin by pancreatic beta cells that signals meal-related satiety through receptors in the hindbrain, slows gastric emptying, and suppresses postprandial glucagon release. Eloralintide is an amylin analogue conjugated to a C20 fatty diacid, which enables reversible albumin binding and a plasma half-life long enough to support once-weekly subcutaneous injection. Its defining design feature is receptor selectivity: in Lilly's in vitro work (Molecular Metabolism, 2025) eloralintide activated the human amylin 1 receptor with approximately 12-fold greater potency than the calcitonin receptor and approximately 11-fold greater potency than the amylin 3 receptor. Earlier amylin analogues such as cagrilintide activate calcitonin receptors alongside amylin receptors; the stated rationale for selectivity is improved gastrointestinal tolerability, supported in rats by significantly less conditioned taste avoidance than cagrilintide. In a 48-week Phase 2 trial (The Lancet, 2025; n=263 across 46 centres in the United States) adults aged 18 to 75 with obesity, or with overweight and at least one weight-related comorbidity, and without type 2 diabetes, were randomised to once-weekly subcutaneous placebo or to eloralintide at 1 mg, 3 mg, 6 mg or 9 mg, or to 6-9 mg and 3-9 mg dose-escalation arms. On the prespecified primary (efficacy) estimand, mean weight reduction at week 48 was 9.5% at 1 mg, 12.4% at 3 mg, 17.6% at 6 mg and 20.1% at 9 mg, against 0.4% on placebo; the 6-9 mg escalation arm reached 19.9% and the 3-9 mg arm 16.4%. Mean baseline weight was 109.1 kg and mean BMI 39.1 kg/m2. Weight reduction began within the first four weeks and no clear plateau was reached in any eloralintide arm by week 48. Secondary measures improved across BMI, waist circumference, blood pressure, lipid profile, glycaemic markers and high-sensitivity C-reactive protein; in a DXA substudy approximately 60 to 70 percent of the mass lost was fat. The most common adverse events were mild-to-moderate gastrointestinal symptoms and fatigue, both more frequent at higher doses. Pooled across eloralintide arms (n=208, versus 52 on placebo), nausea occurred in 32.7% of participants, fatigue in 26.9%, and constipation and diarrhoea in 14.9% each. Discontinuation due to adverse events was 10.1% on eloralintide versus 7.7% on placebo, and serious adverse events occurred in 5.3% versus 5.8%, none judged treatment-related, with no deaths. Lilly reported that slower dose escalation improved tolerability, with adverse event rates in the 1 mg and 3 mg arms similar to placebo. Eloralintide has not been approved by the FDA and no marketing application is on file. Lilly opened the Phase 3 ENLIGHTEN programme between December 2025 and February 2026: ENLIGHTEN-1 (NCT07321886; n=1,980) in obesity or overweight without type 2 diabetes, ENLIGHTEN-2 (NCT07282600; n=1,035) in obesity or overweight with type 2 diabetes, ENLIGHTEN-3 (NCT07369011) in moderate-to-severe obstructive sleep apnoea, ENLIGHTEN-4 (NCT07353931) in knee osteoarthritis, and ENLIGHTEN-6 (NCT07392190) in people with persistent obesity already treated with a weekly incretin. Primary completion for the lead trials falls in 2028, so an approval decision before then is not plausible. Eloralintide is also under study with tirzepatide in a Phase 2 type 2 diabetes trial (NCT06603571) and in a Phase 2b combination trial with macupatide (NCT07589608). Regulatory status verified against FDA sources on 29 July 2026. No human half-life value for eloralintide has been published. The Phase 2 report describes only a long plasma half-life sufficient for weekly dosing, and the Phase 1 proof-of-concept paper (Diabetes, Obesity and Metabolism, 2026) reports dose-proportional steady-state exposure without a terminal half-life figure. Half-life figures of approximately 10 days that circulate alongside eloralintide belong to petrelintide, a different amylin analogue, and should not be attributed to it. Eloralintide access and legal status Because eloralintide has never been approved by the FDA, it is not available on prescription and there is no lawful compounding route. It appears on neither the 503A nor the 503B bulk drug substances list, and an unapproved investigational agent cannot be used as a bulk substance by a compounding pharmacy or outsourcing facility. The only legitimate route of access is enrolment in an active clinical trial. Material sold online under the names eloralintide, LY3841136, or the vendor shorthand Elora is research-grade, is supplied on a not-for-human-consumption basis, and carries unverified identity, purity and sterility. Elora is not an approved name, an International Nonproprietary Name, or a designation used by Eli Lilly. Eloralintide vs cagrilintide: both are long-acting amylin analogues given once weekly by subcutaneous injection, but they differ in receptor selectivity and in development strategy. Cagrilintide (Novo Nordisk) is a non-selective amylin analogue that also activates the calcitonin receptor, and its lead programme is the fixed-dose combination with semaglutide (CagriSema). Eloralintide is engineered for selectivity toward the amylin 1 receptor over the calcitonin receptor, and Lilly has taken it into Phase 3 as a monotherapy first, studying incretin combinations on a separate track. Eloralintide reached 20.1% mean weight reduction at 48 weeks on the efficacy estimand in Phase 2 monotherapy; cagrilintide's monotherapy Phase 2 trial ran to 26 weeks over a different dose range, so the two figures are not directly comparable and no head-to-head trial has been conducted.