A CONTROLLED-STUDY OF THE EFFECTS OF RU58841, A NONSTEROIDAL ANTIANDROGEN, ON HUMAN HAIR PRODUCTION BY BALDING SCALP GRAFTS MAINTAINED ON TESTOSTERANE-CONDITIONED NUDE-MICE

Human hair growth can be monitored for several months after the transp lantation of scalp samples from men with androgen-dependent alopecia o n to female nude mice. Hair production from balding sites has been sho wn to be inhibited in testosterone-conditioned nude mice, We used this recently reported model to study the effect of a new non-steroidal an tiandrogen - RU58841 - on human hair growth, Twenty productive scalp g rafts from balding men were maintained for 8 months after grafting on to nude mice, and hair production was monitored monthly for 6 months, All mice were conditioned by the topical application of testosterone ( testosterone propionate, 300 mu g in 10 mu L; 5 days/week) on the non- grafted flank. The scalp samples were divided equally according to the estimated hair production potential, which was based on the amount of hair present on the scalp samples before grafting. Each of the two eq ual groups of grafts was further allocated at random to be treated top ically (5 days/week) with blinded solutions of either RU58841 1% in et hanol, or ethanol as a control. Twenty-eight active follicles appeared on the 10 control grafts. Among them only two follicles (7%) initiate d a second hair cycle. However the 10 RU58841-treated grafts bore a to tal of 29 active follicles, and eight of them (28%) showed a second cy cle. The Values for the linear hair growth rates (LHGR) were significa ntly (P < 0.04) higher in the RU58841-treated group. Recycling and inc reased LHGR indicate a positive action for RU58841 on human hair growt h from balding samples grafted on to testosterone-conditioned nude mic e, and encourage a clinical trial to evaluate its potential in the tre atment of androgen-dependent alopecia.