Efficacy and safety of dutasteride in the treatment of androgenetic alopecia = Efficacy and safety of dutasteride in the treatment of androgenetic alopecia

다국어 초록 (Multilingual Abstract)

Dutasteride inhibits both type 1 and 2 5-alpha reductases, eventually suppressing DHT in circulation and the target organ. Dutastride was firstly approved for male patten hair loss in Korea since 2009. A. Efficacy - In phase II clinical trial, dutasteride 0.5 mg suppressed DHT concentrations in serum by 92% and in scalp by 51%, while finasteride 5 mg in serum by 73% and in scalp by 41%. Dutasteride 0.5 mg significantly increased hair count versus placebo at 12 and 24 weeks. - In phase III Korean study, dutasteride 0.5 mg showed significantly higher efficacy than placebo group by subject self-assessment and by investigator and panel photographic assessment. There was no major difference in adverse events between two groups. - Recent phase III study with bigger number of subjects (917 men) showed the close dose response in hair count increase across dutasteride 0.02 mg, 0.1 mg and 0.5 mg and added that dutasteride 0.1 mg was non-inferior to finasteride 1 mg and dutasteride 0.5 mg was superior to finasteride 1 mg. B. Safety - It is believed that the adverse events(AE) is related to the DHT suppression. As a result, physicians perceive that the more potent DHT suppression by dutasteride, the more hair growth but the more AEs. - In In phase III Korean study, sexually related AE was not different between dutasteride 0.5 mg group (4.1%) and placebo group (4.0%). - Recent phase III study reported sexual AEs in all active groups (including dutasteride 0.02 mg, 0.1 mg, 0.5 mg and finasteride 1mg) comparing placebo group showed no dose response relationship in dutasteride doses. This study also showed that decreased libido was reported by 9 subjects (4.9%) in dutasteride 0.5 mg group and by 12 subjects (6.7%) in finasteride 1 mg group. - Open label, multi-center, non-interventional observational study in Korea was done from 2009 to 2013. During study period, 712 subjects were enrolled. The subjects of 29.3±6.0 years old exposed to dutasteride for 204.7±161.5 days. Most frequent adverse drug reaction(ADR)s were libido decreased (9, 1.3%), dyspepsia (8, 1.1%), impotence (7, 1.0%), and fatigue (5, 0.7%). Other interested ADRs were sexual function abnormality (4, 0.6%), gynecomastia (2, 0.3%), and ejaculation disorder (1, 0.1%). Most subjects (78.6%) showed overall improvement after treatment of dutasteride in the effectiveness. The sexually related AE in this study is relatively lower than other controlled studies. Like other studies for AGA with dutasteride, this study showed no reports of prostate cancer, breast cancer, or cardiovascular AEs of special interest. The reports on the prognosis of the AEs in alopecia subjects are not found. In the 4-year follow-up of the phase III trials in benign prostate hyperplasia (BPH), the incidence of the sexual AEs was low and tended to decrease over time. Conclusion - Dutasteride increased hair and was relatively well tolerated for the treatment of male pattern hair loss.