What is RU-58841?
RU-58841 is a non-steroidal anti-androgen originally developed by Roussel Uclaf (now part of Sanofi) in the 1970s–80s. It was studied as a topical treatment for androgenetic alopecia (male pattern hair loss) due to its ability to locally block dihydrotestosterone (DHT) from binding to androgen receptors in scalp follicles.
The compound never reached clinical approval, but research interest in its topical anti-androgenic properties has sustained significant study. For research purposes only.
⚠ Research Purposes Only: RU-58841 is not approved for human use by the FDA, MHRA, or any regulatory body. It is sold exclusively as a research chemical for laboratory use.
RU-58841 Research Profile
| Parameter | Research Data |
|---|---|
| Compound Class | Non-steroidal anti-androgen |
| Mechanism | Competitive androgen receptor antagonist |
| Application Route (researched) | Topical (scalp) |
| Half-Life | Short (~2.4 hours, topical metabolite) |
| Systemic Activity | Low when applied topically (research data) |
| Approval Status | Not approved (research only) |
Mechanism — How RU-58841 Works in Research
RU-58841 functions by competitively binding to androgen receptors in the scalp, preventing DHT from occupying those receptors. DHT is the primary androgen responsible for follicle miniaturisation in androgenetic alopecia. By blocking DHT at the receptor level locally, research models have suggested it may slow or arrest follicle miniaturisation without significantly raising systemic DHT levels.
Compared to finasteride (which blocks DHT systemically by inhibiting 5-alpha reductase), RU-58841's topical mechanism is theorised to minimise systemic anti-androgenic side effects. However, in vivo human data is extremely limited.
Comparison with Other Hair Loss Research Compounds
- Finasteride: Systemic 5-alpha reductase inhibitor — reduces DHT body-wide. FDA approved.
- Minoxidil: Vasodilator/potassium channel opener — mechanism partially understood. FDA approved.
- RU-58841: Topical androgen receptor antagonist — local mechanism. Not approved. Research only.
Stability and Solvent Research
One of the key practical research challenges with RU-58841 is its instability in solution over time, particularly in alcohol-based vehicles. Research examining optimal vehicle and storage conditions has shown that ethanol-based solutions can degrade the compound within weeks. MCT oil or propylene glycol-based vehicles tend to show better stability in laboratory conditions.
🔬 Where to Source RU-58841 for Research (USA & UK)
For USA and UK researchers, RCD.bio stocks RU-58841 with third-party certificates of analysis. All products are for research purposes only and not approved for human consumption.
Visit RCD.bio →⚠ Affiliate link — use code Tomjunkie for 20% off. Research purposes only.
Frequently Asked Questions
RU-58841 is researched primarily as a topical anti-androgen for studying androgenetic alopecia (male pattern hair loss). It works by blocking DHT from binding to androgen receptors in scalp follicles. For research purposes only.
No. RU-58841 was never approved by the FDA, MHRA, or any regulatory body. Development was discontinued by Roussel Uclaf. It is available as a research chemical only.
Finasteride blocks 5-alpha reductase systemically to reduce DHT production throughout the body. RU-58841 works locally at the androgen receptor in the scalp, theoretically limiting systemic anti-androgenic effects. However RU-58841 has no human approval and very limited clinical data.
RCD.bio (Research Chemical Depot) is a well-regarded source for RU-58841 with third-party analysis. All products are for research purposes only.