Informational only. Not medical advice.INFORMATIONAL PLATFORM ONLY — NOT MEDICAL ADVICE, DIAGNOSIS, OR TREATMENT
Informational only. Not medical advice.INFORMATIONAL PLATFORM ONLY — NOT MEDICAL ADVICE, DIAGNOSIS, OR TREATMENT
P21 (also P021) is a small peptidergic compound — the tetrapeptide core Asp-Gly-Gly-Leu with an N-terminal acetyl and a C-terminal adamantylated glycine amide (Ac-DGGL(A)G-NH2) — derived from an active region (residues ~148–151) of human ciliary neurotrophic factor (CNTF). It was designed and characterized in the Khalid Iqbal laboratory at the New York State Institute for Basic Research in Developmental Disabilities (NYS IBR). It is an experimental, preclinical compound — NOT FDA-approved and NOT tested in humans in published trials. Distinct from the cyclin-dependent kinase inhibitor protein p21/CDKN1A/WAF1 (a completely different gene product; the two share only the name).
Lowest Price
$79.00
Highest Price
$1071.00
Average Price
$301.60
Potential Savings
67%
across 5 options
1 of 5 vendors are lab-verified for P21
We cross-check each vendor's Certificate of Analysis against the issuing lab's own verification portal — so “cheapest” isn't the only signal.
Best price trend
Lowest $/mg for P21 · last 35 days
$7.90/mg
flat
Trust grade first, cheapest within grade
vial · 10mgskyepeptides.com· price updated today
Lot P2125-10-001· tested 2025-09-03
$7.90/mg
vial · 10mgverifiedpeptides.com· price updated today
Lot P2106260210B· tested 2026-06-05
$11.90/mg
34% more per mg
vial · 120mgatomiklabz.com· price updated today
$8.93/mg
11% more per mg
vial · 12mgsolutionpeptides.net· price updated today
$9.92/mg
20% more per mg
vial · 5mggeneticpeptide.com· price updated yesterday
$24.00/mg
67% more per mg
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Evidence is preclinical (rodent) only. Key publication: Kazim, Blanchard, Dai, Tung, LaFerla, Iqbal & Iqbal, Neurobiology of Disease 2014 (PMID 25046994) reported that chronic oral P021 rescued cognition, boosted dentate-gyrus neurogenesis, and reduced tau hyperphosphorylation in 3xTg-AD mice. Additional preclinical papers from the Iqbal group (and collaborators) have shown dendritic/synaptic rescue in AD and aging rodent models (e.g., Kazim et al., Alzheimer's Res Ther 2017). No Phase 1/2/3 human trials have been published; no human safety or pharmacokinetic data exist. Grey-market vendor material is unvalidated — purity, identity, and dosing are not verifiable.
This platform provides informational tools only, not medical advice.
Prices verified as of June 2026. Actual prices may vary. For research use only.
Prices are estimates and may vary. For research use only. We may earn a commission on purchases through affiliate links. Not medical advice.
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