The Peptide AppThe Peptide App

The Peptide AppField Guide · Healing SeriesSpecimen No. 21

Healing Category

P21

THE NEUROGENESIS BOOSTER

Neurotrophic Peptide P21; CNTF Analog

P21 is an engineered peptide based on ciliary neurotrophic factor (CNTF) that can cross the blood-brain barrier and promote neurogenesis, the growth of new brain cells. It boosts BDNF (brain-derived neurotrophic factor) and has shown promise for cognitive enhancement, Alzheimer's prevention, and stroke recovery.

P21
P21
P21

P21 Evidence Snapshot

How these guides are reviewed
Regulatory status
Not FDA approved · research use only
Dosing guidance
Reviewed by our clinical team
Linked evidence
1 research sources
Content updated
Aug 28, 2026

Dose and schedule recommendations shown below come from The Peptide App Clinical Team. Research links are provided so readers can inspect the supporting evidence directly. Review the sources.

Quick Answers About P21

Is P21 FDA approved?

No. This profile records P21 as not FDA approved and for research use only.

More context

Review the regulatory and source details on this page for the current context.

What dose does The Peptide App Clinical Team recommend for P21?

Dose: 10 mg daily (subcutaneous, intramuscular, or oral).

More context

Schedule: daily. Cycle: 8 weeks on, 8 weeks off. This is clinical-team guidance for reference and does not replace individualized instructions from a licensed clinician.

What research supports this P21 guide?

This guide links to 1 curated or current research sources.

More context

Open the research section to inspect the source titles, publication details, study types, and available abstracts directly.

Review the P21 research sources

Studied Effects & Mechanisms

Neurogenesis

Promotes growth of new neurons in the hippocampus

BDNF Boost

Upregulates brain-derived neurotrophic factor

Anti-Amyloid

Reduces amyloid-beta and tau pathology

Synaptic Plasticity

Enhances NMDA receptor activity for learning

Who is this for

Those concerned about cognitive decline
People wanting to enhance memory and focus
Those with family history of Alzheimer's
Stroke recovery patients

Research-Market Price Snapshot

A compact market signal for this profile. The dedicated pricing page owns vendor, vial-size, and price-per-mg comparisons.

Updated Aug 29, 2026

Vendors
8
Listings
9
Observed range
$61$198
Compare all P21 prices →

Market evidence

P21 product testing and COAs

Current certificates are on file for 4 of 9 vendors tracked in the P21 market. Research on this page describes the molecule. Vendor certificates concern particular market samples or batches; they do not change the research evidence or establish clinical safety, sterility, or suitability for use.

P21 Research

Live research temporarily unavailable

The live research feed did not return papers for this page. The curated references below remain available for crawlable source context.

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