FOXO4-DRIvsP21
FOXO4-DRI vs P21 — independent comparison of uses, administration, pricing across providers, and key differences. Last reviewed April 21, 2026.
Quick Verdict
Based on clinical evidence and real patient data
A D-amino acid retro-inverso peptide designed to disrupt the interaction between FOXO4 and p53 in senescent cells, triggering apoptosis of these 'zombie cells.' A first-in-class senolytic peptide with potential to clear senescent cell burden.
A 21-amino-acid peptide that mimics the action of ciliary neurotrophic factor (CNTF). Studied for neurogenesis, cognitive improvement, and neuroprotection. Shows promise in animal models for enhancing memory consolidation and protecting against neurodegenerative decline.
Best choice depends on your insurance, budget, and treatment history.Take the quiz to get a personalized recommendation.
FOXO4-DRI vs P21: At a Glance
Full comparison across all key factors.
| Factor | FOXO4-DRI | P21ALLY PICK |
|---|---|---|
| Category | anti-aging | cognitive |
| Also Known As | Senostatin, FOXO4-p53 DRI peptide | CNTF analog, Colostrinin fragment |
| Administration | Subcutaneous injection | Intranasal spray |
| Prescription | Required | Required |
| Providers | 2 providers | 3 providers✓ Better |
| Common Uses |
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Data sourced from FDA prescribing information and peer-reviewed clinical trials. Prices reflect telehealth platform costs as of April 21, 2026. See our methodology.
Pricing by Provider
2 providers offer both FOXO4-DRI and P21.
| Provider | FOXO4-DRI | P21 | Consultation | Lab Testing |
|---|---|---|---|---|
 | $450/per-cycle | $180/monthly | Video Telehealth | Yes |
 | $550/per-cycle | $230/monthly | Video Telehealth | Yes |
 | Not offered | $55/one-time | Async Telehealth | No |
Key Differences
FOXO4-DRI
A D-amino acid retro-inverso peptide designed to disrupt the interaction between FOXO4 and p53 in senescent cells, triggering apoptosis of these 'zombie cells.' A first-in-class senolytic peptide with potential to clear senescent cell burden.
P21
More ProvidersA 21-amino-acid peptide that mimics the action of ciliary neurotrophic factor (CNTF). Studied for neurogenesis, cognitive improvement, and neuroprotection. Shows promise in animal models for enhancing memory consolidation and protecting against neurodegenerative decline.
Which Is Right for You?
Choose FOXO4-DRIif…
- You want a anti-aging medication
- You prefer subcutaneous injection administration
- 2 providers available on our platform
- Your primary goal is senescent cell clearance
- Your primary goal is tissue rejuvenation
Choose P21if…
- You want a cognitive medication
- You prefer intranasal spray administration
- You want more provider options (3 available)
- Your primary goal is neurogenesis
- Your primary goal is memory consolidation
Frequently Asked Questions
What is the difference between FOXO4-DRI and P21?
Which is cheaper, FOXO4-DRI or P21?
Can I switch from FOXO4-DRI to P21?
Medical Disclaimer
This comparison is for informational purposes only and does not constitute medical advice. Always consult with a qualified healthcare provider before starting, stopping, or changing any medication. Individual results may vary. The information presented reflects publicly available data and may not account for your specific health situation.