Amycretin Evidence Guide
Amycretin, now called zenagamtide, is one of the most interesting next-generation obesity peptides because it combines GLP-1 and amylin agonism in a single molecule and has both oral and injectable programs. Phase 3 development is underway, but there is no Phase 3 outcome data yet, so it remains behind approved agents and behind retatrutide for near-term evidence.
Our Take
Amycretin, now called zenagamtide, is one of the most interesting next-generation obesity peptides because it combines GLP-1 and amylin agonism in a single molecule and has both oral and injectable programs. Phase 3 development is underway, but there is no Phase 3 outcome data yet, so it remains behind approved agents and behind retatrutide for near-term evidence.
- Best for
- Weight loss research, oral GLP-1/amylin dual agonism pharmacology, obesity treatment development
- Evidence grade
- Level B
- Confidence
- Moderate
- Starting point
- Clinical-trial only; Phase 3 oral and subcutaneous dose protocols are under development
Benefits and Evidence
- Body Weight Reduction: Level B, includes human evidence - Phase 1/2 data showed up to 13% body weight loss at 12 weeks with subcutaneous formulation, exceeding the rate of weight loss observed with semaglutide at comparable timepoints.
- Appetite Suppression: Level B, includes human evidence - Dual receptor agonism provides robust appetite suppression through complementary brainstem and hypothalamic pathways. Patient-reported hunger and food intake significantly reduced.
- Gastrointestinal Tolerability: Level B, includes human evidence - Nausea and vomiting are common side effects consistent with the GLP-1 and amylin agonist class. Dose titration strategy is being optimized to improve tolerability.
Side Effects and Warnings
- Nausea (most common)
- Vomiting
- Diarrhea
- Decreased appetite
- Constipation
- Investigational agent - not yet approved for clinical use
- Long-term safety and efficacy data not yet available
- GI side effects may limit tolerability at higher doses
Research Dosage References
- <strong>Subcutaneous injection</strong> - Dose-escalation (specific doses not yet disclosed) - Once weekly (anticipated) - Phase 2 trials ongoing. Dose-titration approach used to mitigate GI side effects. Oral formulation also in development.
- <strong>Oral</strong> - Under investigation - Once daily (anticipated) - Oral amycretin formulation in Phase 2 trials. If successful, would offer significant convenience advantage over injectable therapies.
Mechanism of Action
Amycretin provides dual appetite suppression through two complementary pathways: 1. GLP-1 receptor agonism: Activates GLP-1 receptors in the pancreas (enhancing glucose-dependent insulin secretion), hypothalamus (reducing appetite), and GI tract (slowing gastric emptying). 2. Amylin receptor agonism: Activates amylin receptors (calcitonin receptor + RAMP1/2/3 complex) in the area postrema and other brainstem regions, providing additional satiety signaling distinct from GLP-1 pathways. 3. Synergistic appetite suppression: The dual mechanism targets complementary neural circuits controlling food intake - GLP-1 primarily in hypothalamic and reward centers, amylin primarily in hindbrain satiety centers. 4. Glucose homeostasis: Both pathways contribute to improved glycemic control through enhanced insulin secretion, glucagon suppression, and delayed gastric emptying.
Legal Status
Investigational new drug. Novo Nordisk has advanced zenagamtide/amycretin into Phase 3 development for weight management in 2026; it is not approved by any regulatory authority and is not available outside clinical trials.
Primary Sources
- Safety, tolerability, and pharmacokinetics of amycretin in overweight or obese adults: a phase 1 study. ClinicalTrials.gov, 2023.
- Amycretin, a dual amylin and GLP-1 receptor agonist, for weight management: phase 2 results. Obesity, 2024.
- Dual amylin and calcitonin receptor agonists: new therapeutic targets for obesity and metabolic disease. Br J Pharmacol, 2015.