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ToolsCompareP21 vs Cagrilintide

P21 vs Cagrilintide

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

Cognitive EnhancementAnti-Aging & Longevity
P21
GLP-1 / Weight Loss Agonists
Cagrilintide
Summary
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.
Cagrilintide is a long-acting amylin analog developed by Novo Nordisk. Amylin is a peptide hormone co-secreted with insulin from pancreatic beta cells. Cagrilintide slows gastric emptying, suppresses glucagon, and reduces appetite via central amylin receptors. In combination with semaglutide (CagriSema), Phase 2 trials achieved approximately 15% body weight reduction. Phase 3 trials (REDEFINE program) are ongoing.
Half-Life
Not well characterized; likely short, but neurogenic effects persist long after administration
~7–10 days
Admin Route
SubQ, Intranasal
SubQ
Research
Typical Dose
100–500 mcg
0.16 mg → 0.3 mg → 0.6 mg → 1.2 mg → 2.4 mg
Frequency
Once daily
Once weekly
Key Benefits
  • 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
  • ~15% body weight reduction in combination with semaglutide (CagriSema Phase 2)
  • Synergistic appetite suppression complementing GLP-1 receptor agonists
  • Reduces post-meal glucagon excursions improving glycemic control
  • Slows gastric emptying contributing to prolonged satiety
  • Once-weekly dosing via subcutaneous injection
  • Potential for greater weight loss than semaglutide monotherapy
Side Effects
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
  • Nausea (most common, especially during titration)
  • Vomiting
  • Decreased appetite
  • Diarrhea
  • +2 more
Stacks With