Finasteride in the treatment of men with androgenetic alopecia☆,☆☆
Section snippets
Study population (Tables IA and IB)
Empty Cell US phase III initial study International phase III initial study Finasteride 1 mg (n = 471) Placebo (n = 462) Finasteride 1 mg (n = 308) Placebo (n = 312) Age (y, mean ± SE) 33 ± 0.2 34 ± 0.2 31 ± 0.3 31 ± 0.3 Age at which hair loss began (y, mean ± SE) 24 ± 0.2 25 ± 0.2 24 ± 0.3 24 ± 0.3 No. (%) of patients with family history* 373 (80) 363 (80) 227 (74) 239 (77) Baseline hair count (mean ± SE)† 864 ± 11 856 ± 12 916 ± 15 924 ± 14 No. (%) of
EVALUATION PROCEDURES
Four predefined efficacy end points provided a comprehensive assessment of changes in scalp hair from baseline.
LABORATORY EVALUATION
Hematology, urinalysis, chemistry, and hormone measurements were performed at baseline and every 6 months. Serum chemistry, including prostate-specific antigen (PSA), and serum hormones, including testosterone, DHT, luteinizing hormone, and follicle-stimulating hormone, were assayed in central laboratories (Medical Research Laboratories, Highland Heights, Ky, and Endocrine Sciences, Calabasas Hills, Calif, respectively).
STATISTICAL ANALYSIS
A data analysis plan prespecified all primary and secondary hypotheses, including combining data from both initial studies, to improve precision of the estimates of treatment effect, and from both extension studies, because of the small size of the placebo groups in the extension phase.
The primary hypothesis for hair counts was assessed by the difference between the count at each time point and the accompanying baseline count, and mean values for each treatment group were determined by means of
RESULTS
Patient accounting is summarized in Fig 1.
ADVERSE EVENTS
Clinical adverse events considered by the investigator to be possibly, probably, or definitely drug-related that occurred in 1% of men or more are shown in Table IV. In the first year, a slightly higher proportion of finasteride-treated than placebo-treated patients reported adverse events related to sexual function (4.2% vs 2.2%, P < .05; see Table IV for details). Only 11 men (1.4%) in the finasteride group and 8 (1.0%) in the placebo group discontinued the study because of sexual adverse
DISCUSSION
In these studies, finasteride treatment produced significant improvements in scalp hair in men with male pattern hair loss. The efficacy of finasteride was evident within 3 months of therapy. Hair count, first measured at 6 months, progressively increased over 1 year in the finasteride group, and the improvement was maintained through the second year. In contrast, the placebo group progressively lost hair, consistent with the miniaturization process and the natural history of male pattern hair
Acknowledgements
We acknowledge the technical assistance of Mr. Douglas Canfield, of Canfield Scientific, Inc, in the development of photographic procedures used in these clinical studies. We also thank Dr O’Tar Norwood for permission to use drawings in the clinical study protocols that first appeared in his article “Male Pattern Baldness: Classification and Incidence” (South Med J 1975;68:1359-65).
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Reprint requests: Keith D. Kaufman, MD, Merck Research Laboratories (RY33-500), 126 E Lincoln Ave, Rahway, NJ 07065.
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0190-9622/98/$5.00 + 0 16/1/92149
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The Finasteride Male Pattern Hair Loss Study Group includes (in alphabetical order) R. Asarch, N. Birchall, I. H. Boersma, S. Brenner, K. Bruno, D. Buntin, G. Burg, J. Cilliers, P. Cotterill, W. J. Cunliffe, D. Ferguson, V. Fiedler, D. Fivenson, T. Funicella, C. Gencheff, D. Gratton, W. He, S. Horwitz, J. Imperato-McGinley, F. Jurado Santa-Cruz, I. Katz, A. P. Kelly, D. Kopera, P. Kotey, J.-M. Lachapelle, M. Ling, E. Lopez-Bran, N. Lowe, A. Lucky, S. MacDonald Hull, A. McDonagh, C. Mork, G. Peck, E. Prens, P. Reygagne, R. Rietschel, R. Rittmaster, E. Round, T. Rufli, N. Sadick, P. Saiag, P. Sanchez-Pedreno, J. B. Schmidt, M. Sher, J. Shupack, D. Steiner, D. Stewart, M. Stiller, D. Stough, J. Swinehart, L. Swinyer, G. Todd, W. Unger, J. Waldstreicher, G. Weinstein, D. Weiss, J. Weiss, S. E. Whitmore, and H. Wolff.