PP405
An experimental topical gel that aims to wake dormant hair-follicle stem cells by changing how they use energy. It is not approved.
PP405 Biological Classification
Investigated within physiological and chemical models.
What kind of compound
Small molecule
Investigational topical small molecule.
Human testing on file
1human record
0 animal · 1 total indexed. Phase 2 trials registered or reported.
Regulatory position
Investigational. No approved product; Phase 2a completion is not an approval.
Studied for
Follicle stem-cell reactivation
Reviewed 13 November 2026
Known safety concerns in this file
- Phase 1 reported the product was well tolerated with no detectable systemic absorption, per the sponsor.
- Phase 2a safety results are not available here as a peer-reviewed report.
- Long-term safety is unknown.
Commonly compared with
- Minoxidil — Approved topical treatment with a different mechanism.
- Pyrilutamide — Investigational topical androgen-receptor blocker.
- SM04554 — Investigational Wnt-pathway approach.
What is PP405?
An experimental topical gel that aims to wake dormant hair-follicle stem cells by changing how they use energy. It is not approved. An investigational topical gel developed by Pelage Pharmaceuticals that inhibits the mitochondrial pyruvate carrier to activate dormant hair-follicle stem cells. It has completed a Phase 1 study and a Phase 2a trial in androgenetic alopecia, with a further Phase 2 trial registered in women. It is not an approved drug.
Why are people interested in it?
Most hair-loss drugs slow androgen-driven miniaturisation. PP405 is testing a different idea: reactivating follicles that have gone quiet.
Primary Research Categories
- Hair-follicle research
- Investigational drug substances
How does it work in the body?
Inhibits the mitochondrial pyruvate carrier (MPC), shifting cellular metabolism and activating dormant follicle stem cells in laboratory and early human biopsy work. This is a proposed mechanism with early human biomarker support, not proof of hair regrowth.
Biological Pathway Overview
PP405 Receptor & Target Interactions
This compound is evaluated in scientific research for its interactions with target cellular receptors and signaling cascades. Consult the evidence section below for specific peer-reviewed papers.
Mitochondrial pyruvate carrier
Named in the published mechanism discussion for this compound.
Lactate dehydrogenase
Named in the published mechanism discussion for this compound.
Follicle stem-cell activation
Named in the published mechanism discussion for this compound.
Telogen-to-anagen transition
Named in the published mechanism discussion for this compound.
Key Distinction: An investigational or unapproved compound has no approved indication, and a proposed mechanism is not a demonstrated clinical effect.
What has actually been demonstrated in humans?
Phase 1 and a completed Phase 2a trial in androgenetic alopecia; a Phase 2 trial in women is registered. Therapept has not indexed a peer-reviewed primary publication of the Phase 2a results.
Pharmaceutical Reality vs. Unregulated Research Chemicals
Investigational. No approved product; Phase 2a completion is not an approval. Peer-reviewed Phase 2a efficacy and safety results.
What is still uncertain or unknown?
Peer-reviewed Phase 2a efficacy and safety results. Durability after treatment stops. Phase 3 confirmation and any regulatory decision.
Research at a Glance
Open the full evidence file (1 records)1 record in this file
- CLINICAL TRIAL1
Publication span: 2024
What Has Actually Been Studied
- Safety, pharmacokinetics and efficacy of PP405 in adults with androgenetic alopecia (PP405-2001) (ClinicalTrials.gov, 2024) — Phase 2a randomised, vehicle-controlled trial with open-label extension (registry record).
What is Still Unknown
What we know
Editorial reading of the records below, labelled as Therapept analysis. How records are built
What remains uncertain
Preparation and Handling
Lyophilized peptides ship as freeze-dried powders; whatever happens next involves diluents, concentrations and storage conditions that are compound- and product-specific.
United States Regulatory Status
Investigational
- No approved United States product in Drugs@FDA as of this review.
- Phase 2a trial NCT06393452 (PP405-2001) is registered as completed; the registry record describes a randomised, vehicle-controlled study with an open-label extension.
- Phase 2 trial NCT07907783 in adult females with androgenetic alopecia was registered in 2026 with a not-yet-recruiting status at review.
- Therapept has not indexed a peer-reviewed primary publication of the Phase 2a results. Sponsor presentations and press releases are not a substitute for a published trial report or an approval.
Technical Chemical SpecificationsClick to view CAS, sequence, and molecular formulas
- Molecular weight
- Unknown
- Sequence length
- Not recorded
- CAS number
- Unknown
- PubChem CID
- None assigned
- Compound class
- Investigational topical small molecule; inhibitor of the mitochondrial pyruvate carrier (MPC)
- Sequence
- Unknown / Unassigned
- Molecular formula
- Unknown
- Molecular weight
- Unknown
- CAS number
- Unknown
- PubChem CID
- Unknown
Sources
Last reviewed 13 November 2026 · Compiled by Therapept Editorial · How these records are built