Canada: Findings from a meta-analysis, published in the journal JAMA Dermatology contribute to the comparative effectiveness literature for androgenetic alopecia (AGA) therapies with regard to the compared interventions.
"With the accumulation of efficacy data from head-to-head trials, there could be a better sense of the relative efficacy of 5-α reductase inhibitors and minoxidil' different doses," Aditya K. Gupta, Mediprobe Research Inc, London, Ontario, Canada, and colleagues wrote in their study.
Androgenetic alopecia is a common form of hair loss in both men and women. The enzyme 5-α reductase is convolved in the etiologic factors in this condition.
There are knowledge gaps regarding the relative efficacy of 3 commonly used drugs for androgenetic alopecia AGA, namely, the two 5-α reductase inhibitors finasteride and dutasteride, and minoxidil. To fill this knowledge gap, Dr. Gupta and his team conducted the study to examine the relative efficacy of any dose and administration route of minoxidil, dutasteride, and finasteride for the treatment of male AGA.
For this purpose, the researchers performed systematic searches in PubMed on March 5, 2021. The studies that investigated monotherapy with any dose and administration route of minoxidil, dutasteride, and finasteride were deemed eligible for the meta-analysis.
Following 2 stages of screening, 23 studies were eligible for quantitative analyses from 848 records obtained from PubMed search. The mean age of patients ranged from 22.8 years to 41.8 years.
Study endpoints were changes in total and terminal hair count after 24 and 48 weeks of therapy. The 4 endpoints were quantified in hairs per square centimeters.
Following were the study's key findings:
The greatest increase in total hair count at 24 weeks (ie, first endpoint) was with 0.5 mg/d of dutasteride, which was significantly more efficacious than 1 mg/d of finasteride (mean difference, 7.1 hairs/cm2) and minoxidil (0.25 mg/d, 5 mg/d, and 2% solution).
The greatest increase in terminal hair count at 24 weeks (ie, second endpoint) was with 5 mg/d of minoxidil, which was significantly more efficacious than the 0.25-mg/d dose (mean difference, 43.6 hairs/cm2) and its topical forms (in 2% and 5%); 5 mg/d of minoxidil was significantly more efficacious than 1 mg/d of finasteride.
The greatest increase in total hair count at 48 weeks (ie, third endpoint) was with 5 mg/d of finasteride (mean difference, 10.4 hairs/cm2), which was significantly more efficacious than 2% topical minoxidil (mean difference, 20.7 hairs/cm2).
The greatest increase in terminal hair count at 48 weeks (ie, fourth endpoint) was with 1 mg/d of finasteride, which was significantly more effective than topical minoxidil (in 2% [mean difference, 32.1 hairs/cm2] and 5% [mean difference, 26.2 hairs/cm2]).
"The findings of this meta-analysis contribute to the comparative effectiveness literature for AGA therapies with regard to the compared interventions," the authors concluded.
Reference:
Gupta AK, Venkataraman M, Talukder M, Bamimore MA. Relative Efficacy of Minoxidil and the 5-α Reductase Inhibitors in Androgenetic Alopecia Treatment of Male Patients: A Network Meta-analysis. JAMA Dermatol. Published online February 02, 2022. doi:10.1001/jamadermatol.2021.5743