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ToolsCompareSurvodutide vs P21

Survodutide vs P21

Side-by-side comparison of key properties, dosing, and research.

GLP-1 / Weight Loss Agonists
Survodutide
Cognitive EnhancementAnti-Aging & Longevity
P21
Summary
Survodutide is a once-weekly GLP-1/glucagon dual receptor agonist developed by Boehringer Ingelheim and Zealand Pharma. Phase 2 trials demonstrated up to 18.7% body weight reduction at 46 weeks, among the highest reported for a dual agonist. It is being studied for obesity and MASH (metabolic dysfunction-associated steatohepatitis), where the glucagon component drives hepatic fat clearance.
P21 is a synthetic peptide derived from CNTF (ciliary neurotrophic factor) that promotes hippocampal neurogenesis, enhances memory and spatial learning, and may reduce amyloid-beta pathology. It is used as a neurogenic and cognitive enhancer with potential anti-Alzheimer's applications.
Half-Life
~7 days
Not well characterized; likely short, but neurogenic effects persist long after administration
Admin Route
SubQ
SubQ, Intranasal
Research
Typical Dose
0.6 mg → 2.4 mg → 4.8 mg → 6 mg
100–500 mcg
Frequency
Once weekly
Once daily
Key Benefits
  • Up to 18.7% body weight reduction at 46 weeks (Phase 2)
  • Strong MASH activity — Phase 3 SYNCHRONIZE-NASH trials ongoing
  • Reduces hepatic fat content via glucagon receptor-driven liver oxidation
  • Once-weekly subcutaneous injection
  • Greater weight loss potential than GLP-1 monotherapy
  • Improvements in liver fibrosis markers in early data
  • Promotes hippocampal neurogenesis
  • Enhances spatial memory and learning
  • Increases BDNF expression
  • Reduces amyloid-beta plaque formation (animal models)
  • Anti-tau pathology potential
  • Cognitive enhancement without stimulant effects
  • Potential therapeutic for Alzheimer's and cognitive aging
Side Effects
  • Nausea (most common during titration)
  • Vomiting
  • Diarrhea
  • Decreased appetite
  • +3 more
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
Stacks With