RU-58841 Powder | 2 Grams

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RU-58841 Powder — 2 Grams

RU-58841, also designated PSK-3841 or HMR-3841, is a non-steroidal
anti-androgen (NSAA) that acts as a competitive antagonist of the androgen receptor. It is not a selective androgen
receptor modulator (SARM); it blocks rather than activates the receptor. This listing is a
research-grade reference compound supplied in powder form for in vitro and
laboratory investigation. Identity and purity are third-party verified and documented by a downloadable
Certificate of Analysis.

• 99.31% purity (HPLC)
• Third-party verified
• 2,050 mg net
• Public COA
• UV-resistant foil pouch

Research Context

RU-58841 was developed by Roussel Uclaf in the early 1990s as a non-steroidal androgen receptor antagonist
designed for local rather than systemic activity. Its initial characterization reported high affinity for the
androgen receptor and evaluated its local anti-androgenic activity in the hamster flank organ, a standard model
of androgen-dependent skin tissue.^[1] Subsequent studies used it as an experimental tool in
androgen-dependent hair follicle models, including human scalp grafts maintained on testosterone-conditioned nude
mice^[2] and a primate model alongside androgen-responsive prostate cancer cells.^[3] The
compound has not been evaluated in published large-scale human trials, and its long-term safety profile is not
established.

This material is supplied strictly as a reference compound to support such laboratory investigation. It is
not a therapeutic product, dietary supplement, or sports supplement, and no clinical or
performance outcomes are claimed or implied for any individual.

Scientific References

1. Battmann T, Bonfils A, Branche C, et al. RU 58841, a new specific topical antiandrogen: a candidate of choice for the treatment of acne, androgenetic alopecia and hirsutism. J Steroid Biochem Mol Biol. 1994;48(1):55–60.
2. De Brouwer B, Tételin C, Leroy T, Bonfils A, Van Neste D. A controlled study of the effects of RU58841, a non-steroidal antiandrogen, on human hair production by balding scalp grafts maintained on testosterone-conditioned nude mice. Br J Dermatol. 1997;137(5):699–702.
3. Pan HJ, Wilding G, Uno H, et al. Evaluation of RU58841 as an anti-androgen in prostate PC3 cells and a topical anti-alopecia agent in the bald scalp of stumptailed macaques. Endocrine. 1998;9(1):39–43.
4. Van Wagoner RM, Eichner A, Bhasin S, Deuster PA, Eichner D. Chemical Composition and Labeling of Substances Marketed as Selective Androgen Receptor Modulators and Sold via the Internet. JAMA. 2017;318(20):2004–2010.