Topical minoxidil is the only US FDA approve drug for the treatment of female pattern hair loss. The maximum strength of the legally marketed topical minoxidil in the US (5% minoxidil topical foam) is effective in regrowing hair in only a minority of women i.e., approximately 30%; thus, the majority of female pattern hair loss patients remain untreated.
Previously, we have demonstrated that non-responder to 5% topical minoxidil foam are low metabolizers of minoxidil; thus we hypothesized that increasing the bioavailable minoxidil to low metabolizers will increase the number of responders to topical minoxidil without increasing the rate of adverse events. In this study, we recruited female pattern hair loss subjects that were identified as non-responders to 5% topical minoxidil foam utilizing the previously reported sulfotransferase assay.
A novel topical solution of 15% minoxidil was applied daily during 3 months. Preliminary results of our pilot study have demonstrated clinically significant response based on hair counts increase from baseline (over 15%) as well as global photographic assessment compared to baseline. None of the subjects experienced significant hemodynamic changes.
To the best of our knowledge, this is the first study to demonstrate the potential beneficial effect of higher concentration of minoxidil in female pattern hair loss subjects that fail to respond to topical 5% minoxidil.