Mazdutide
Also called IBI362; LY3305677; OXM3
A dual GLP-1/glucagon receptor agonist approved in China in 2025 for weight management and type 2 diabetes. It is not approved in the US, and the FDA has acted against unapproved products sold here.
Overview
What it is
A once-weekly peptide developed by Innovent under license from Eli Lilly.
How it works
The GLP-1 component lowers appetite and blood sugar; the glucagon component is intended to increase energy use. That distinguishes it from GLP-1-only drugs like semaglutide.
What the research shows
Phase 3 GLORY-1 (NEJM, 2025) and GLORY-2 (JAMA, 2026) studied Chinese adults with obesity. In DREAMS-1 (320 adults with type 2 diabetes), HbA1c fell 1.6 to 2.2 points at 24 weeks versus 0.1 with placebo. In open-label DREAMS-3, the sponsor reported 10.3% weight loss versus 6.0% with semaglutide 1 mg at 32 weeks. A US phase 2 trial was published in 2026.
Studied for
- Obesity and overweightphase 3, approved in China
- Type 2 diabetesphase 3, approved in China
Safety and regulatory status
Safety and side effects
In GLORY-2's highest-dose group, vomiting occurred in 53%, nausea in 47% and diarrhea in 39%, versus 1% to 7% on placebo. In the US phase 2 trial, 20% of the highest-dose group stopped because of side effects. Persistent vomiting, dehydration or severe abdominal pain needs medical attention.
Regulatory status
Approved in China (NMPA, 2025). Not FDA approved; FDA named marketed mazdutide products in an August 2026 warning letter.
Mixing and dosing reference
Reference information only. Read before using this section.
Mazdutide (5 mg Vial) Dosage Protocol
- Vial
- 5 mg Mazdutide
- Add diluent
- 3 mL
- Concentration
- 1.67 mg/mL
- 1 unit (U-100)
- 16.67 mcg in 0.01 mL
- Route
- Subcutaneous
- How often
- Once per week (subcutaneous injection).
- Typical range
- 2.5–6 mg weekly with gradual titration; advanced protocols may reach 10 mg.
- Cycle length
- Minimum 8 weeks; clinical evidence supports 12–48 week protocols.
Standard / Gradual Titration
| Week | Weekly Dose | Units (per injection) (mL) |
|---|---|---|
| Weeks 1–4 | 2.5 mg (2,500 mcg) | 150 units (1.50 mL) |
| Weeks 5–8+ | 5 mg (5,000 mcg) | 300 units (3.00 mL) |
Advanced / High-Dose Protocol (mixed with 2 mL, 2.5 mg/mL)
| Week | Weekly Dose | Units (per injection) (mL) | Notes |
|---|---|---|---|
| Weeks 1–4 | 5 mg (5,000 mcg) | 200 units (2.00 mL) | 1 vial |
| Weeks 5–8 | 7.5 mg (7,500 mcg) | 300 units (3.00 mL) | 1.5 vials |
| Weeks 9–12+ | 10 mg (10,000 mcg) | 400 units (4.00 mL) | 2 vials; split into 2 injections |
How to mix
- Draw 3.0 mL bacteriostatic water with a sterile syringe.
- Inject slowly down the vial wall; avoid foaming.
- Gently swirl until dissolved (do not shake vigorously).
- Label with date and refrigerate at 2–8 °C (35.6–46.4 °F), protected from light.
Dosing details
- Start: 2.5 mg once weekly for first 4 weeks to establish tolerability.
- Increase: Advance to 5 mg weekly at week 5; maintain for remainder of protocol (weeks 5–12+).
- Frequency: Once per week (subcutaneous injection).
- Cycle Length: Minimum 8 weeks; clinical evidence supports 12–48 week protocols.
- Timing: Administer on the same day each week; rotate injection sites to avoid irritation.
Storage
- Lyophilized: Store at −20 °C (−4 °F) or below in dry, dark conditions; protect from moisture.
- Reconstituted: Refrigerate at 2–8 °C (35.6–46.4 °F); bacteriostatic water does not establish peptide stability or a universal use-by period.
- Important: Do not freeze reconstituted solution; avoid freeze–thaw cycles which can denature the peptide.
- Discard: Follow the specific product’s validated use-by period. Discard if cloudiness or particulates appear.
Administration technique
- Subcutaneous injection guidance based on clinical best practices.
- Clean the vial stopper and injection site with alcohol swabs; allow to air‑dry completely.
- Use aseptic technique: wipe stoppers, use sterile needles, and avoid touching needle tip.
- Pinch a skinfold and insert the needle at 45–90° into subcutaneous fatty tissue (not muscle).
- Do not aspirate for subcutaneous injections; inject slowly and steadily over 5–10 seconds.
- Withdraw needle and apply gentle pressure with a clean swab; do not rub vigorously.
- Rotate injection sites systematically: abdomen (at least 2 inches from navel), front/outer thighs, or outer upper arms.
- For volumes >3 mL, divide dose into two injections at separate sites for comfort and absorption.
Important notes
- Use a new sterile insulin syringe for each weekly injection; dispose in a proper sharps container.
- Rotate injection sites weekly (abdomen, thighs, upper arms) to minimize local irritation and lipoatrophy.
- For doses requiring >3 mL volume, split into two separate injections at different sites for comfort and absorption.
- Allow reconstituted vials to reach room temperature before withdrawing dose to reduce viscosity.
- Document dose, injection site, and any side effects to track response and optimize protocol.
Protocol source: PeptideDosages.com
Common questions
Is mazdutide better than semaglutide?
It produced more weight loss than semaglutide 1 mg in one open-label diabetes trial; it has not been compared to higher semaglutide doses.
Is it approved in the US?
No.
Why do reports show different percentages?
Trials use different statistical analyses; check which one a headline uses.
Related in Metabolic Health
Sources and further reading (6)
- Innovent Biologics. China approval announcements, June and Sept 2025.
- Once-weekly mazdutide in Chinese adults with obesity (GLORY-1). NEJM, 2025.
- Mazdutide 9 mg in Chinese adults with obesity (GLORY-2). JAMA, 2026.
- Zhu D, et al. Mazdutide vs placebo in type 2 diabetes (DREAMS-1). Nature, 2026.
- FDA. Warning letter on unapproved products including mazdutide, Aug 24, 2026.
- Source summary: PeptideDosages.com research overview (rewritten for NVO).
Laboratory research material: Mazdutide Research Use Only