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.
Identity and purity are independently confirmed by MZ Biolabs (Tucson, AZ), a US DEA Schedule III licensed analytical facility (License RP0584676), using HPLC purity analysis and mass-spectrometry identity confirmation under Good Laboratory Practice (GLP) standards to support research reproducibility.
Current certificate of analysis for RU-58841, issued by MZ Biolabs. Tap to view full size.
Open or download the current RU-58841 COA · View the full COA archive →
Store in a cool, dry place away from direct sunlight to maximize shelf life. Supplied in a UV-resistant foil pouch to minimize photodegradation.
Independent analysis has repeatedly found that research compounds sold online are frequently mislabeled or adulterated. A 2017 JAMA investigation that chemically analyzed products marketed as SARMs and related research compounds found that only a minority accurately matched their labeled contents, and a substantial share contained unapproved or entirely different substances.[4] Third-party testing is the control that distinguishes a documented reference compound from an unverified one.
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.
RU-58841 is an investigational compound that has not been approved by the U.S. Food and Drug Administration for any use and cannot be prescribed or dispensed by pharmacies. It is not a dietary supplement, drug, or cosmetic, and marketing it for human use by any route is unlawful. It is supplied exclusively for laboratory research purposes.
For laboratory research use only. This preparation is not approved by the FDA for human use. RU-58841 is not a dietary supplement, drug, or cosmetic and is not intended for human or animal use by any route.
All products on this website are intended exclusively for research and development purposes. The statements herein have not been evaluated by the U.S. Food and Drug Administration. Neither the statements nor the products are intended to diagnose, treat, cure, or prevent any disease. Sports Technology Labs are chemical suppliers, not medical practitioners; our expertise is sourcing and quality control.
| Weight | 0.25 oz |
|---|---|
| Dimensions | 3 × 0.3 × 4 in |
