Eloralintide is a long-acting, selective amylin receptor agonist developed by Eli Lilly. In a 48-week phase 2 trial (Lancet, 2025) once-weekly subcutaneous doses of 1-9 mg produced average weight loss of 9.5% to 20.1%, compared with 0.4% on placebo. A 10 mg vial reconstituted with 3.0 mL bacteriostatic water gives 3.33 mg/mL.
- Selective amylin receptor agonist, not a GLP-1 drug.
- About 12 times more selective for amylin receptors than calcitonin receptors.
- Fatty-acid attachment allows once-weekly dosing.
- Phase 2: 9.5-20.1% average weight loss at 48 weeks vs 0.4% placebo.
- Investigational only; phase 3 trials started in late 2025.
Reconstitution
Vial strength
10 mg
Bacteriostatic water
3 mL
Concentration
3.33 mg/mL
1 unit = 0.01 mL = 33.3 mcg (U-100 syringe)
- 1Draw 3.0 mL bacteriostatic water with a sterile syringe.
- 2Inject the water slowly down the inside wall of the vial to prevent foaming.
- 3Gently swirl or roll the vial until fully dissolved; do not shake.
- 4Label with the date and refrigerate at 2-8 °C (35.6-46.4 °F), protected from light. Use within 4 weeks.
Dosing schedule
| Phase | Dose | On a U-100 syringe |
|---|---|---|
| Weeks 1-4 | 1 mg | 30 units (0.30 mL) |
| Weeks 5-8 | 3 mg | 90 units (0.90 mL) |
| Weeks 9-12 | 6 mg | 90 units (0.90 mL) x 2 injections |
| Weeks 13+ | 9 mg (highest studied dose) | 90 units (0.90 mL) x 3 injections |
Protocol detail
| Start | Begin with 1 mg once weekly for 4 weeks, the lowest dose studied in phase 2. |
|---|---|
| Escalate | Step up to 3 mg, then 6 mg, then 9 mg, staying at least 4 weeks on each dose. The trial also used escalation arms (3 to 6 to 9 mg); exact step lengths here follow research-community convention. |
| Target | Hold at the lowest dose that works. 9 mg was the highest dose studied. |
| Frequency | Once per week, subcutaneously, on the same day each week. |
| Cycle Length | The phase 2 trial ran for 48 weeks. |
Overview at a glance
| Goal | Reduce appetite and body weight through amylin receptor activation. |
|---|---|
| Schedule | Once-weekly subcutaneous injection, stepping up the dose every 4 weeks. |
| Dose Range | 1-9 mg weekly (doses studied in phase 2: 1, 3, 6 and 9 mg). |
| Reconstitution | 3.0 mL per 10 mg vial (~3.33 mg/mL). |
| Storage | Lyophilized frozen at -20 °C; reconstituted refrigerated at 2-8 °C and used within 4 weeks. |
How it works
Amylin is a hormone released with insulin after meals that slows stomach emptying and signals fullness to the brain. Eloralintide mimics amylin at its receptors, reducing appetite and food intake. It is engineered with a fatty-acid side chain that binds albumin in the blood, extending its action so it can be given once a week. Because it works through a different pathway from GLP-1 drugs, it is also being studied alongside them.
Reported effects
- Average weight loss of 9.5-20.1% at 48 weeks in phase 2, depending on dose
- Weight loss had not plateaued at the higher doses by the end of the trial
- Once-weekly dosing
- Reported to have a low rate of gastrointestinal side effects compared with GLP-1 drugs
Reported side effects
- Nausea
- Vomiting
- Diarrhea or constipation
- Reduced appetite
- Fatigue
- Injection site reactions
- Gastrointestinal effects were mostly mild and occurred mainly during dose increases
Storage
Lyophilised (unmixed)
Store frozen at -20 °C (-4 °F) in dry, dark conditions; minimize moisture exposure.
After reconstitution
Refrigerate at 2-8 °C (35.6-46.4 °F); use within 30 days and avoid freeze-thaw cycles.
Supplies
| Peptide vials | About 1 vial for the first 8 weeks (1 mg then 3 mg); at 9 mg weekly one vial covers about 1 week. |
|---|---|
| Syringes | U-100 insulin syringes for doses ≤72 units (Weeks 1-6); 3 mL syringes with 25-27G needles for doses >100 units (Weeks 7+); 1 syringe per week. |
| Bacteriostatic Water | 1 x 10 mL bottle for 8-12 weeks; 2 x 10 mL bottles for 16 weeks (3.0 mL per vial). |
| Alcohol Swabs | 2 per week (one for vial, one for injection site); recommended 1 x 100-count box for 16-week protocol. |
Important notes
- Always use a new, sterile syringe for each injection and dispose of it in a sharps container.
- Rotate injection sites weekly (abdomen, thighs, upper arms) to minimize local skin irritation.
- Gradual dose increases are crucial for managing potential gastrointestinal side effects.
- Keep a record of your weekly dose, injection site, and any adverse reactions.
- For doses exceeding 1.0 mL, use a 3 mL syringe with an appropriate subcutaneous needle instead of a U-100 insulin syringe.
Frequently asked questions
How is Eloralintide different from Cagrilintide?
Both are long-acting amylin-based peptides given once a week. Cagrilintide (Novo Nordisk) acts on both amylin and calcitonin receptors, while Eloralintide (Eli Lilly) is designed to be much more selective for amylin receptors.
How much weight was lost in the trial?
In the 48-week phase 2 trial of 263 adults with obesity or overweight, average weight loss ranged from 9.5% to 20.1% across the dose groups, compared with 0.4% on placebo (Billings et al., Lancet 2025).
Is Eloralintide approved?
No. It is investigational and entered phase 3 trials in late 2025. It is sold for laboratory research only.
How should it be stored once mixed?
Keep it in the fridge at 2-8 °C, protected from light, and use within 4 weeks.
Educational reference only. These figures summarise how Eloralintide is commonly described in research literature and supplier documentation, including the Eloralintide listing at peptidesuk4u.co.uk. They are not a prescription, not medical advice, and not a recommendation to self-administer anything.
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