MariTide (AMG-133) Reconstitution Calculator
Enter the amount you want to measure. The vial buttons will highlight which vial strengths create cleaner syringe-unit measurements.
What amount do you need?
Type the target amount, then choose mg or mcg. Example: 2mg or 500mcg.
Syringe size:
Possible vial strengths:
Best Match
Good Match
Usable
Harder to Measure
Example MariTide (AMG-133) Titration Schedule
| Parameter | Details |
|---|---|
| Typical Dosage (Phase 2) | Monthly dosing: 140 mg, 280 mg, 420 mg; Every 8 weeks: 420 mg |
| Starting & Escalation (Phase 3) | 21 mg → 35 mg → up to 350 mg (8-week titration) |
| Route of Administration | Subcutaneous (SC) injection |
| Frequency | Monthly (every 4 weeks) or less frequent (e.g., every 8–12 weeks) |
| Cycle Length | Clinical trials up to 104 weeks (~2 years) of treatment |
| Half‑Life | Extended half-life (~13–17 days); supports extended dosing intervals |
| Reconstitution | Supplied as solution; typically no reconstitution required |
Possible vial strengths:
What Is It?
MariTide (AMG-133)
GLP-1 agonist / GIPR antagonist conjugate.
Bacteriostatic Water
Sterile water containing a bacteriostatic preservative, commonly used when preparing multi-use research vials.
How To Mix MariTide (AMG-133)
1
CleanUse alcohol swabs to clean the tops of both vials.
2
Draw BAC WaterDraw the selected amount of bacteriostatic water.
3
Inject SlowlyAdd the liquid slowly down the side of the vial.
4
Swirl GentlyDo not shake. Swirl gently until dissolved.
5
Store ProperlyStore as directed and protect from heat and light.
Best Practices & Common Mistakes
Best Practices
- Use sterile technique.
- Protect from light and heat.
- Store refrigerated when appropriate.
- Use clean syringe-unit math before measuring.
Common Mistakes
- Confusing milligrams with milliliters.
- Choosing an option with awkward decimal units.
- Using too little liquid for very small measurements.
- Shaking the vial aggressively.
MariTide (AMG-133) Storage & Handling
Lyophilized Powder: −20°C (−4°F) for long-term storage (up to 24 months). Refrigeration 2–8°C (36–46°F) for short-term use (up to ~3 months). Original sealed vial in the freezer is safest.
Reconstituted Solution: 2–8°C (36–46°F), use within ~7–14 days. Keep sealed, avoid light, and do not repeat freeze-thaw cycles.
Reconstituted Solution: 2–8°C (36–46°F), use within ~7–14 days. Keep sealed, avoid light, and do not repeat freeze-thaw cycles.
Frequently Asked Questions
MariTide, also called maridebart cafraglutide or AMG 133, is an investigational obesity drug from Amgen. It is a long-acting antibody-peptide conjugate designed for monthly or less frequent dosing, but it is not FDA-approved or commercially available.
MariTide activates the GLP-1 receptor while blocking the GIP receptor. That is different from tirzepatide, which activates both GLP-1 and GIP receptors, making MariTide a distinct incretin-based approach rather than a copy of existing GLP-1/GIP drugs.
A calculator can only show concentration math, not a clinical dosing plan. For example, if a hypothetical 420 mg research vial is brought to 7 mL final volume, the concentration is 60 mg/mL; 140 mg equals 2.33 mL, 280 mg equals 4.67 mL, and 420 mg equals 7.00 mL.
Yes. Amgen has multiple Phase 3 MARITIME studies evaluating MariTide for chronic weight management and obesity-related conditions. Phase 3 status does not mean approval; MariTide is still investigational until regulators review and approve it.
Tirzepatide is a GLP-1/GIP dual agonist given weekly, while MariTide combines GLP-1 activation with GIP receptor blocking and is being studied for monthly or less frequent dosing. The tradeoff is that tirzepatide is already approved, while MariTide still needs Phase 3 outcomes and regulatory review.
Practical takeaway: If your real goal is weight or metabolic health, the most useful next step is discussing approved treatment options with a clinician rather than relying on an unapproved compound.
Important: This tool is for informational and research-reference purposes only. Not intended for human or veterinary use.