P21 vs Cagrilintide
A detailed comparison to help you understand the differences and choose the right peptide for your research goals.
P21
P21 is a synthetic peptide derived from Cerebrolysin, specifically designed to mimic the neurotrophic effects of the parent compound. It promotes neurogenesis and has shown cognitive-enhancing properties in research.
Full details →Cagrilintide
Cagrilintide is a long-acting amylin analog in development, showing promising results when combined with semaglutide (CagriSema). Amylin is a hormone co-secreted with insulin that promotes satiety.
Full details →Side-by-Side Comparison
| Aspect | P21 | Cagrilintide |
|---|---|---|
| Mechanism | Inhibits glycogen synthase kinase-3β (GSK-3β) and activates CREB signaling pathway. This promotes BDNF expression, neurogenesis in the hippocampus, and synaptic plasticity. | Activates amylin receptors (calcitonin receptor with RAMP proteins) to slow gastric emptying, suppress glucagon secretion, and reduce food intake through central satiety mechanisms distinct from GLP-1. |
| Typical Dosage | Research protocols typically use 1-5mg administered intranasally or subcutaneously. Often used in cycles of 2-4 weeks. | Clinical trials: 2.4mg weekly as monotherapy or in combination with semaglutide 2.4mg (CagriSema). Optimal dosing still being determined. |
| Administration | Can be administered intranasally for direct CNS access or subcutaneously. Best used cyclically rather than continuously. | Subcutaneous injection once weekly. Currently only available in clinical trials - not yet FDA approved. |
| Side Effects | Limited data. Reported effects include mild headache, temporary brain fog during initial use, and fatigue. | Nausea, vomiting, diarrhea, constipation similar to other incretin-based therapies. Combination with semaglutide may increase GI effects initially. |
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