PTD-DBM

What PTD-DBM is

The name describes the structure. PTD stands for Protein Transduction Domain, a transport sequence that carries the peptide into cells. DBM stands for Dishevelled Binding Motif, the segment of the protein CXXC5 with which it docks onto the signaling protein Dishevelled.

PTD-DBM was developed in Choi’s research group at Yonsei University in Seoul, first for wound healing (2015), then for hair growth (2017). All work on the peptide comes from this group.

What is rated is the state of knowledge. For PTD-DBM, it reaches as far as the mouse.

How it works

The Wnt/β-catenin signaling pathway controls the growth and formation of new hair follicles. The protein CXXC5 acts as a brake in it: it binds to Dishevelled and thereby dampens the signal. PTD-DBM competes with CXXC5 for this binding, the brake is released, β-catenin rises. Together with valproic acid, a drug that activates the same pathway at a different point, the effect in animals was stronger.

The link to humans comes from the original paper: in bald areas of the scalp, more CXXC5 was found in miniaturized hair follicles and in the arrector pili muscles, and in human dermal papilla cells CXXC5 suppressed growth markers in the laboratory (Lee 2017). In 2023, the same group described CXXC5 in mice as a link in the chain through which the androgen DHT and the tissue hormone prostaglandin D2 trigger hair loss (Ryu 2023).

What the studies show

Lee 2015: wound healing

In the original paper (J Exp Med), CXXC5 was reduced in fresh human skin wounds, and mice without CXXC5 healed faster. PTD-DBM activated β-catenin and collagen production in the laboratory; together with valproic acid it accelerated wound healing in mice.

Lee 2017: hair growth

The paper in J Invest Dermatol linked CXXC5 to hair: more CXXC5 in balding human scalp, suppressed human dermal papilla cells in the laboratory, faster hair growth in mice without CXXC5. PTD-DBM activated the Wnt pathway and, in mice, accelerated the regrowth of hair and the formation of new follicles in wounds. A commentary in the same journal classified CXXC5 as a new regulator of the Wnt pathway (Kim and Garza 2017).

Ryu 2023: DHT and prostaglandin D2

Prostaglandin D2 triggers hair loss. In mice, switching off CXXC5 or PTD-DBM reversed this hair loss, and the formation of new follicles in wounds also returned (Cells). Hair loss triggered by DHT was alleviated in animals by simultaneous inhibition of GSK-3β and CXXC5.

Fan 2026: the classification

The review in Biomedicines places PTD-DBM alongside other hair peptides. In combination with valproic acid it worked more strongly in mice than minoxidil in the same experiment. The review also notes that minoxidil, finasteride and dutasteride are approved, PTD-DBM is not.

Where the data stop

• Nothing in humans. There is no study on the effect on the scalp, none on tolerability and none on whether the peptide passes through the skin into the follicle. No trial is listed in the ClinicalTrials.gov registry.
• One research group. All data on PTD-DBM come from the group in Seoul. An independent replication is missing.
• From mouse fur to a bald head. What was measured was the regrowth of mouse fur. Whether that transfers to hereditary hair loss in humans has not been tested.
• The strongest effects with valproic acid. The clearest findings come from the combination with valproic acid, a prescription-only drug. These experiments say nothing about what PTD-DBM alone would do in humans.

Status, approval and legal

PTD-DBM is not approved as a medicine anywhere, neither in Germany nor in the EU or the US, and no trial is listed in the ClinicalTrials.gov registry. It is offered as a research peptide on the gray market. We do not give dosage information for unapproved substances.

For hereditary hair loss there are approved agents with large studies in humans, such as finasteride.

Safety

There are no safety data in humans. The main open question is what sustained activation of the Wnt/β-catenin pathway does in the skin. The same research group writes in 2025 that agents acting on this pathway are developed only cautiously because of its concerning role in cancer, and found it activated in samples of cutaneous squamous cell carcinoma (Lee 2025). Whether PTD-DBM touches on this risk has not been studied.

In addition, with products from peptide shops it is not assured that purity and content are correct.

Sources

• Lee SH et al., J Invest Dermatol 2017 – CXXC5 and hair growth, PTD-DBM in a mouse model
• Kim D, Garza LA, J Invest Dermatol 2017 – commentary on the CXXC5 paper
• Lee SH et al., J Exp Med 2015 – CXXC5 slows wound healing, PTD-DBM in a mouse model
• Ryu YC et al., Cells 2023 – CXXC5 mediates DHT- and prostaglandin D2-induced hair loss (mouse)
• Fan C et al., Biomedicines 2026 – review of short peptides for hair loss, PTD-DBM with animal data only
• Lee SH et al., Exp Mol Med 2025 – Wnt/β-catenin in cutaneous squamous cell carcinoma
• ClinicalTrials.gov – search for PTD-DBM, no registered trial