An independent peptide reference — no sellers, every claim sourced

PTD-DBM

Also known as Protein Transduction Domain-Dishevelled Binding Motif, CXXC5-Dvl inhibitor peptide, PTD-DBM peptide

Cell-penetrating peptide for hair regrowth via CXXC5-Dishevelled disruption; one mouse study, no human data.

preclinical Skin & cosmetic research chemical

At a glance

Category
Skin & cosmetic
Status
research chemical
Route
topical to the scalp in the mouse work and in unvalidated human self-experimentation, usually in a solution mixed by the user
Half-life
No published pharmacokinetics in any species, by any route
Sequence
A protein transduction domain fused to a short motif from the CXXC5 protein that binds Dishevelled. Published renderings of the exact construct differ between sources and are not reproduced here.

PTD-DBM is not a registered medicine, not a cosmetic ingredient with an INCI name, and not an approved treatment for hair loss anywhere. It has no investigational new drug status that has been made public and does not appear as an intervention in any registered clinical study: a search of the ClinicalTrials.gov registry in July 2026 returns zero studies for the term 3. Its commercial position is unusual and worth naming: it is sold as a raw peptide by research-chemical vendors and mixed at home by members of hair-loss forums, typically with topical valproic acid, while being almost entirely absent from finished consumer products. Most compounds on this site travel from laboratory to product to consumer; this one skipped the middle step.

Doping status: Not listed by name; as a non-approved substance it falls under S0 and is therefore prohibited at all times.

Checked against the WADA 2026 Prohibited List. For a specific product and country, Global DRO is the lookup athletes are expected to use — the List names substances, not brand names.

This is a short entry. There is little or no published research on this compound, so there is correspondingly little to report. Empty dosing or reconstitution sections mean no credible figures exist — not that they were left out.

Mechanism of action

The Wnt/beta-catenin pathway drives hair follicle development and the transition into anagen, the growth phase. CXXC-type zinc finger protein 5 acts as a negative regulator of that pathway by binding Dishevelled, and it is upregulated in miniaturised follicles and arrector pili muscles in human balding scalp 1. PTD-DBM is a competitor: the Dishevelled-binding motif occupies the interaction site so that CXXC5 cannot, the brake on Wnt signalling is released, and beta-catenin signalling in the follicle rises. The protein transduction domain is the delivery half — a cell-penetrating sequence intended to carry the motif across the membrane to reach an interaction that is entirely intracellular.

The peptide is usually discussed together with valproic acid because that is how it was studied. Valproic acid inhibits glycogen synthase kinase 3 beta, which activates the same pathway at a different point, and the original work combined the two so that the brake was released and the accelerator pressed at once 1. That is a coherent design. It is also the reason a user combining the two cannot attribute anything they observe to the peptide, since valproic acid alone activates Wnt signalling and has its own literature in hair regrowth.

What the research shows

One mouse and cell-culture study, published in a good journal, plus follow-up work from the same laboratory in wound healing. There is no human data of any kind: no trial, no case series, no pharmacokinetics, no tolerability data, and no registered study 3. Anyone applying this is not using a treatment with thin evidence; they are using one with no human evidence at all.

Research in humans

No published human studies. None. No clinical trial appears in PubMed or ClinicalTrials.gov as of July 2026 3. There is no published report of PTD-DBM having been applied to a human scalp under any protocol, no data on how much of a topically applied cell-penetrating peptide reaches the follicle, and no safety observation in a person. The self-reported experiences circulating on hair-loss forums are not evidence and are almost always confounded by concurrent minoxidil, finasteride, dutasteride, microneedling or valproic acid.

Animal and lab research

Lee and colleagues (Journal of Investigative Dermatology, 2017) identified CXXC5 as a negative regulator of Wnt/beta-catenin signalling acting through Dishevelled, showed it was upregulated in human balding scalp, demonstrated inhibitory effects on alkaline phosphatase activity and proliferation in human hair follicle dermal papilla cells, and reported that CXXC5-knockout mice showed accelerated hair regrowth which valproic acid further increased. Disrupting the CXXC5-Dishevelled interaction with a competitor peptide activated the pathway and accelerated hair regrowth and wound-induced hair follicle neogenesis in mice 1. It is a careful mechanistic paper and it identifies a target; it is not a demonstration that a topical product works in people. The same laboratory later reported PTD-DBM combined with valproic acid in an adhesive hydrogel patch for regenerative wound healing in mice 2. Both papers include authors affiliated with a company founded to commercialise the work, which should be read alongside the results rather than instead of them.

Caveats. The entire case is a rodent and cell-culture study. Mouse hair follicle cycling is synchronised and its response to Wnt activation is not a reliable model for androgenetic alopecia in humans, where the follicle is miniaturised under androgen pressure rather than simply held out of anagen. Nearly a decade after the original paper, no clinical trial of PTD-DBM has been registered 3, which in a field with substantial commercial interest in hair-loss treatments is itself informative. There is no chronic toxicology, no immunogenicity assessment and no data on what deliberately activating Wnt/beta-catenin signalling in scalp skin does over years — a pathway whose dysregulation is implicated in several cutaneous tumours. Grey-market material is additionally of unverified identity and purity.

What it is used for

  • Preclinical research tool for probing the CXXC5-Dishevelled interaction and Wnt-dependent hair follicle regeneration 12
  • Sold as a raw peptide by research-chemical vendors and mixed at home for topical scalp application, usually alongside topical valproic acid, with no validated formulation, concentration or safety data
  • Essentially absent from finished consumer hair products, which is a meaningful signal: an ingredient popular enough to have a following but which no manufacturer has been willing to put its name to in a regulated product

Protocols

Home scalp 'protocol' with valproic acid (user-reported)

user protocol — not validated

Source: Hair-loss forum posts extrapolating a single 2017 mouse study; no published human basis

This is not a validated schedule. It is a pattern that circulates among users and sellers, reproduced because it is what people actually follow — not because it has been tested. No trial established these doses, this interval or this duration, and nobody is checking what is in the vial. Treat every number below as an assertion, not a finding.

Core of the routinePTD-DBM in a home-mixed topical solution applied to the scalp, almost always together with topical valproic acid
Usually stacked inmicroneedling, and concurrent minoxidil and/or finasteride or dutasteride
Concentration and frequencynot agreed among users; PeptideX supplies no figure because none has a published basis

This 'protocol' is a direct extrapolation of one mouse and cell-culture study 1, in which the peptide was paired with valproic acid to release the Wnt brake and press the accelerator at once. Users reproduce the pairing, but nothing in the study establishes a human concentration, vehicle or dose, and no figure is given here for that reason. Because valproic acid alone activates Wnt signalling and has its own hair-regrowth literature, and because minoxidil, finasteride and microneedling are usually added as well, no user can attribute an observation to the peptide. Topical valproic acid is a prescription antiepileptic and a known human teratogen absorbed through broken skin, which is the more concrete hazard in the combination than the peptide itself.

Schedules are reproduced as their source states them. Units, IU and milligrams explains why the figures are not interchangeable between products.

Reconstitution

No formulation or concentration guidance is given here, because giving it would imply that a defensible human protocol exists. It does not. Solutions and vehicles described in forum posts are user inventions, and no published study establishes what concentration of a cell-penetrating peptide reaches a human hair follicle from a topical vehicle, or whether the peptide survives in that vehicle at all.

Safety

Side effects

  • Unknown in humans — no person has been monitored on this compound in any published study
  • The mouse work reports no tolerability findings that transfer to human scalp use
  • Local irritation is a general expectation of any home-mixed topical scalp solution, and is more often attributable to the vehicle, the solvent or the co-applied valproic acid than to the peptide
  • Deliberate long-term activation of Wnt/beta-catenin signalling in skin is a mechanism-based concern that no study has examined in people
  • The absence of reported side effects reflects the absence of humans in the literature, not safety

Do not use if

  • Everyone, in the practical sense: there is no indication for which the risk-benefit ratio has been established in a human being
  • Any current, past or suspected skin malignancy — the compound acts by de-repressing a proliferative signalling pathway and its behaviour in that setting is entirely unstudied
  • Pregnancy and breastfeeding, and any possibility of pregnancy where topical valproic acid is co-applied — valproate is a known human teratogen and the combination is the way this peptide is normally used
  • Children and adolescents: no data, and a mechanism that manipulates a developmental signalling pathway is a poor candidate for use during growth
  • Broken, inflamed or freshly treated scalp skin, including after microneedling, which greatly increases delivery of an unstudied compound

Interactions

Not studied in humans. The one relationship examined at all is with valproic acid, and only in mice 12: the two act on the same pathway at different points and were designed to be used together. Topical valproic acid carries its own risks, including systemic absorption through damaged scalp skin and teratogenicity, and is a prescription antiepileptic rather than a cosmetic. Interactions with minoxidil, finasteride or dutasteride have never been examined, and combined use makes any personal observation uninterpretable.

Sources