The Novel Drug CS-891 Inhibits 5alpha-Reductase Activity in Freshly Isolated Dermal Papilla of Human Hair Follicles

The study investigated the effects of the novel drug CS-891 on 5alpha-reductase (5aR) activity in the dermal papillae of human hair follicles, which is relevant to the treatment of androgenetic alopecia (AGA). 5aR is responsible for converting testosterone to dihydrotestosterone (DHT), a process implicated in AGA. While finasteride, a selective type II 5aR inhibitor, was known to reduce circulating DHT by 60-70% in men, it did not affect type I 5aR activity. CS-891 was identified as a compound with dual inhibitory activity on both isoenzymes, suggesting its potential effectiveness in preventing or treating AGA by inhibiting 5aR activity in hair follicles.