RU5884 is capable of blocking 70% from DHT binding by inhibiting the androgen receptor. When compared with the anti-androgen cyproterone acetate RU58841 showed 20% increased binding to the androgen receptor.
In a study researchers compared the anti-androgen effects of RU58841 with other known anti-androgens like hydroxyflutamide and biculatamide in human prostate cells and showed that RU58841 demonstrated similar effects.
In another study researchers applied 5% topical RU58841 to the bald scalp of stumptail macaques. The stumptail macaques who were treated with RU58841 displayed progression from telogen to anagen and an increase in hair follicle size as opposed tot he control group. No systemic side effects were reported in the study. They described RU58841 as having ““remarkable effects on hair and folliclar regrowth in the bald frontal scalp of macaques.”
Researchers performed another study on the macaque model where they examined the effects of RU58841 versus finasteride. They looked at follicular regrowth and serum level of T and DHT. They concluded that RU58841 appeared to suppress T/DHT induced follicular regression more effectively than finasteride. RU58841 also did not induce any significant changes on T and DHT levels.
After the 6 month human clinical trial they had the following to say about RU58841:
“Six months of treatment with PSK 3481 demonstrated equivalent or better net hair growth compared with finasteride”
Taken all this it is assumable that RU58841 works just as well as finasteride but simply with a different mode of action. Furthermore, it does not seem to alter the hormone profile. However long term studies on the effectiveness of RU58841 are missing.
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- BATTMAN 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.
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