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P21
Neuroprotective & Cognitive EnhancersP21 is an investigational tumor-targeting peptide under preclinical development for oncology and neurotherapeutics. It acts by penetrating cancer cells via CXCR4 or similar receptors and may disrupt mitochondrial energy production. It is also being evaluated for cell-penetrant cargo delivery and cognitive enhancement.
Reconstitute
2 mL BAC + 5mg vial
25 mcg/unit
Daily Range
100–500 mcg Subcutaneous (SQ)
Dependent on clinical trial design and indication
Standard Dose
250 mcg
Cycle
4–8 weeks
then reassess
P21cancer targetingcell-penetrating peptideCXCR4tumor selectivity
Dosing & Reconstitution Guide
Doses used in early-stage rodent studies range from 250–500 μg/kg administered intranasally or intraperitoneally. P21 has no clinical use authorization.
Standard / Gradual Approach
standardPhaseDoseVolume
Week 1100mcg
Week 2200mcg
Week 3300mcg
Week 4400mcg
Protocol Summary
Subcutaneous (SQ): Dependent on clinical trial design and indication · Dose range 100–500 mcg with gradual titration
Cycle Length: 4–8 weeks typical; reassess before extending
Frequency & Cycling
SubQ Injection
Research-based peptide. Frequency and cycle duration determined by protocol in tumor or neurodegenerative studies.
🧪 Quick Start
BAC Water
2 mL
Potential Benefits & Use Cases
P21 is a research compound under investigation for CNS applications. Not approved for human use.
May activate neural stem cells in rodent brain tissue
Studied for enhancing memory formation and learning
Investigated for anti-aging effects on the central nervous system
Explored for use in traumatic brain injury and cognitive recovery models
Still in early research phase with no clinical trial data available
Clinical data Strong preclinical Limited data
Mechanism of Action
→Tumor-specific internalization through CXCR4 receptor targeting
→Cell-penetrating peptide (CPP) architecture
→May inhibit mitochondrial ATP production in cancer cells
→Potential to deliver therapeutic cargos into malignant cells
Lifestyle & Optimization
timing
Consistent daily dosing.
diet
Antioxidant-rich diet with berries, green tea, and cruciferous vegetables. Avoid smoking.
exercise
Exercise regularly 4–5 times weekly.
sleep
Sleep 7–9 hours nightly for cellular repair. Manage stress.
Peptide Research & Preclinical Studies
Evidence-Based Research Findings
Side Effects & Safety
Common Side Effects
• Injection site discomfort
Contraindications & Warnings
• Potential immunogenicity in some patients
• Effects on non-target cells in high systemic concentrations
Long-Term Safety Data
• Unknown due to lack of human trials
🧮 Dose Calculator
Concentration
25.0
mcg/unit
Draw Volume
20
units (0.200 mL)
For a 500 mcg dose, draw 20 units on a U-100 insulin syringe
🧬
Bioavailability & Absorption
SubQ Injection
Efficient tissue penetration demonstrated in preclinical tumor models
Oral Administration
Not suitable due to poor gastrointestinal stability
Half-Life
Varies depending on structure and PEGylation/cyclization modifications
Degradation
Primarily via hepatic enzymes; stability enhanced by structural modifications
Tissue Specificity
Designed for CXCR4-overexpressing tumor cells and inflamed tissues
⚗️
Peptide Details
Molecular Weight
629.76
Formula
C31H47N9O7
Sequence
Sequence varies; representative motif includes cell-penetrating and targeting domains
⚖️
Legal Status & Regulatory
RegionStatus
FDANot Approved
EUNot Approved
AustraliaNot Approved
CanadaNot Approved
Storage Instructions
Lyophilized (Powder)
Store lyophilized powder at 2-8°C
Reconstituted (Mixed)
After reconstitution, maintain at 2-8°C and use within 21 days. Protect from light and temperature fluctuations.