Capixyl (Acetyl Tetrapeptide-3 + biochanin A)

Capixyl is a trademarked, ready-to-formulate cosmetic active marketed by Lucas Meyer Cosmetics (now part of Clariant) for hair and scalp care. It is not a single peptide but a synergistic complex of two parts: acetyl tetrapeptide-3, a lab-made (biomimetic) four-amino-acid signal peptide, and red clover (Trifolium pratense) flower extract standardized for the isoflavone biochanin A. It is supplied as a concentrate (commonly used in finished products at around 5%) and is intended for topical scalp/hair applications such as serums, not for injection or ingestion.

Education only. This page summarises published research on a cosmetic or dietary ingredient. It is not medical advice and makes no treatment claims; for a finished product, follow its label.

Also known as: Capixyl, Capixyl™, Acetyl tetrapeptide-3 + red clover (Trifolium pratense) extract, Acetyl tetrapeptide-3 with biochanin A, biomimetic hair peptide complex
Class: Topical cosmetic biomimetic signal peptide (acetyl tetrapeptide-3) combined with a phytoestrogen/isoflavone 5-alpha-reductase inhibitor (biochanin A from red clover)

How does Capixyl work?

The two components are proposed to act on different drivers of androgenetic ("pattern") hair thinning. Biochanin A is an isoflavone that can inhibit 5-alpha-reductase, the enzyme that converts testosterone into dihydrotestosterone (DHT) — the androgen linked to follicle miniaturization — and may also dampen pro-inflammatory cytokines at the scalp. Acetyl tetrapeptide-3 is a signal peptide thought to stimulate extracellular-matrix proteins (such as collagens and laminin) around the dermal papilla, which the manufacturer says improves anchoring of the hair shaft and supports the follicle's regenerative niche. The intended net effect is a shift of more follicles into the growth (anagen) phase and fewer into the resting/shedding (telogen) phase. These are mechanistic proposals largely from in-vitro and manufacturer data, not fully proven in vivo causal pathways.

What has Capixyl been studied for?

Androgenetic alopecia (male and female pattern hair thinning)
Increasing anagen (growth-phase) hair and reducing telogen (resting-phase) hair
Increasing terminal/total hair density and counts
Supporting hair anchoring and reducing shedding
General scalp/hair cosmetic 'fuller-looking hair' claims

What does the evidence show?

Evidence is limited and should be read with caution. The most cited human data are: (1) a manufacturer (Lucas Meyer) in-house study reporting roughly a 13% increase in anagen hair density and a large drop in telogen hairs versus placebo — industry-sponsored, small (the active arm was only on the order of ~15–17 subjects in critical appraisals), and not independently replicated, with several endpoints not reaching statistical significance; and (2) a peer-reviewed 24-week randomized, triple-blind trial (Lueangarun & Panchaprateep, J Clin Aesthet Dermatol 2020;13(10):32-37, N=32) of a combination of biochanin A, acetyl tetrapeptide-3 AND ginseng extract versus 3% minoxidil, which found a comparable ~8.3% increase in terminal hair counts to minoxidil's ~8.7% (no statistically significant difference between arms). Key caveats: small sample sizes, manufacturer/conflict-of-interest involvement, the published trial added ginseng (so Capixyl's specific contribution cannot be isolated) and used 3% rather than the more common 5% minoxidil as the comparator, and there is no long-term independent data. Overall the signal is "encouraging but not definitive."

What is known about the safety of Capixyl?

As a leave-on topical cosmetic used at typical formulation levels, Capixyl is generally well tolerated, and trials reported no serious adverse events. Possible issues are the usual topical ones: scalp irritation, redness, itching, or contact/allergic reactions — patch testing is sensible. Because biochanin A is a phytoestrogen (isoflavone) and a 5-alpha-reductase modulator, people who are pregnant, breastfeeding, or have hormone-sensitive conditions, as well as anyone on hormonal or hair-loss medications, should discuss use with a clinician; systemic absorption from topical scalp use is expected to be low but is not well characterized. Long-term safety has not been independently established, and red-clover-derived material can be an allergen for those sensitive to legumes/isoflavones. Not for ingestion or injection. This is general education, not medical advice.

What is the legal status of Capixyl?

Legal as a cosmetic ingredient. Capixyl is sold as a cosmetic raw material; its components appear under INCI names (Acetyl Tetrapeptide-3 and Trifolium Pratense (Clover) Flower Extract / biochanin A) and are used in leave-on hair and scalp cosmetics in the US, EU, and other markets. It is NOT an FDA-approved drug and is not approved to treat or cure hair loss; any genuine hair-regrowth (drug) claim would move a product into OTC/Rx drug territory (the category occupied by approved actives like minoxidil and finasteride). It is not a banned or scheduled substance and is not a WADA-prohibited substance.

What is the half-life of Capixyl?

Not characterized/not clinically established for topical use. As a leave-on cosmetic applied to the scalp, a systemic plasma half-life is not a meaningful or reported parameter; short peptides and isoflavones are generally subject to local enzymatic turnover, and the manufacturer specifies routine daily reapplication rather than relying on a measured half-life.

Sources

From the Peppies Peptide Intelligence Library: an educational summary of the published literature, not medical advice. No dosing, preparation or administration instructions are given on these pages. Last updated 2026-09-24. Corrections: support@peppies.eu.