Free UK delivery over £70No customs charges on deliverySame-day dispatch before 2pmCoA with every order
NorwoodLabs
Pillar · PP405

What Is PP405? The Pelage Hair Growth Compound, Explained

The newest serious molecule in the hair-loss research space: a topical that targets follicle stem cell metabolism rather than androgens. Here is what PP405 actually is, what the company has reported, and what is still unpublished.

20 September 2026·7 min read·Research use only
The short version
  • PP405 is Pelage Pharmaceuticals' topical hair growth candidate, targeting follicle stem cell metabolism, not androgens.
  • Phase 2a topline was reported positive in 2025; the full dataset is not yet peer-reviewed.
  • Not approved anywhere. No launched product exists.
  • Mechanically distinct from the antiandrogens: it would not be a substitute for RU-58841 or pyrilutamide, but a different axis entirely.
  • Research use only. Nothing here is medical advice.

What PP405 actually is

PP405 is a small molecule in clinical development for androgenetic alopecia by Pelage Pharmaceuticals. Where RU-58841 and pyrilutamide attack the problem at the androgen receptor, PP405 targets the mitochondrial pyruvate carrier (MPC), the shuttle that moves pyruvate into mitochondria for energy production. The hypothesis, in plain terms: dormant hair follicle stem cells sit in a low-metabolism state, and reactivating their energy metabolism pushes them back into the growth cycle. It is a genuinely different mechanism from every antiandrogen on the market or in this catalogue, which is exactly why it has generated interest: it would stack with, rather than duplicate, the androgen-blocking approach.

What the company has reported so far

Pelage reported positive topline results from its Phase 2a study in 2025: the compound was described as well tolerated with efficacy signals in androgenetic alopecia. What has not happened yet is peer-reviewed publication of the full dataset, including exact hair-count changes, placebo comparisons, and adverse-event tables. Until that exists, the correct reading of PP405 is the same discipline we apply to pyrilutamide's China trial: real, encouraging, company-reported, and not yet independently verified.

Status: not approved, not launched

PP405 has no marketing authorisation in any jurisdiction. It is in clinical development, and nothing containing it is for sale as a finished product anywhere legitimate. The only context in which the molecule appears in commerce is as a reference material for laboratory research, and any seller making treatment claims about it is saying things the clinical programme itself has not yet proven.

Where it sits in the research landscape

The hair-loss research space now has three distinct mechanistic axes: androgen receptor blockade (RU-58841, pyrilutamide, clascoterone), metabolic reactivation (PP405, and the earlier minoxidil lineage), and the systemic DHT suppression represented by finasteride and dutasteride. PP405 is the first genuinely hyped compound in the metabolic bucket since minoxidil itself. For researchers, that makes it a reference point worth understanding even before it is available: its reported profile, if the Phase 2 data holds, would make it a stacking option rather than a replacement for antiandrogens.

The honest bottom line

PP405 is promising, mechanistically novel, and very early. It has one positive company-reported topline, no published dataset, no approval, and no long-term safety record. Nothing we sell substitutes for it, and it substitutes for nothing we sell: it operates on a different axis. Until it is approved, any PP405 in circulation is a research material, and it should be treated with exactly the caution we document for the antiandrogens on the RU-58841 side effects page.

Related reading

For the antiandrogen side of the space, start with What Is RU58841? and What Is Pyrilutamide?, or read the head-to-head in RU-58841 vs Pyrilutamide.

Nothing we sell is a licensed medicine, and no treatment or medical claims are made. All products are research compounds sold strictly for laboratory use.

Reference · FAQ

Frequently asked.

What is PP405?

PP405 is an investigational topical hair growth compound developed by Pelage Pharmaceuticals, a Los Angeles based biotech. It is a small molecule designed to reactivate dormant hair follicle stem cells by targeting the mitochondrial pyruvate carrier (MPC). It is not an antiandrogen and has no hormone-related mechanism.

How is PP405 different from RU-58841 and pyrilutamide?

Mechanism. RU-58841 and pyrilutamide (KX-826) are androgen receptor antagonists: they work by blocking DHT signalling at the follicle. PP405 targets cell metabolism in the follicle's stem cells, so in principle it addresses a different node entirely. Whether that translates to better results on a scalp is unresolved; no head-to-head study exists, or could exist, at this stage.

What did the PP405 Phase 2a trial show?

Pelage announced positive topline results from its Phase 2a trial in 2025, reporting that the compound was well tolerated and showed signs of efficacy in androgenetic alopecia. The detailed dataset has not been published in a peer-reviewed journal yet, so the honest summary is 'company-reported positive topline, details pending'.

Is PP405 approved or available anywhere?

No. PP405 has no marketing authorisation in any country. Pelage is advancing it through clinical development, and no approved or launched product exists. Any offer to sell 'PP405' as a finished product would be an unlicensed research preparation, not an approved treatment.

Why would a lab want PP405 reference material?

For the same reasons research groups buy RU-58841: in vitro characterisation, receptor or pathway work, and analytical method development. The mechanism (mitochondrial pyruvate carrier modulation in follicle stem cells) is actively studied, and reference material lets independent labs verify identity and purity claims.

Does PP405 affect hormones or androgens?

No. It is not an androgen receptor antagonist and is not designed to alter systemic or local hormone levels. Its reported mechanism is metabolic, acting on dormant follicle stem cells. That said, no long-term human safety data exists, so the usual research-compound caution applies.