In the treatment of male androgenetic alopecia (AGA), low-dose dutasteride (0.5 mg/day), used off-label in the United States, tops the ranking of the most commonly used oral and topical agents in a new meta-analysis.
“The results of this meta-analysis indicate that 5 mg daily of oral dutasteride has the highest likelihood of being the most effective treatment,” followed by other ranked agents, the authors report in research published this month. here in JAMA Dermatology.
While up to 90% of men suffer from AGA during their lifetime, only three therapies are currently approved for the treatment of the disease by the United States Food and Drug Administration (FDA): topical minoxidil, oral finasteride 1 mg and low intensity light therapy.
However, with the common use of off-label oral minoxidil, as well as oral dutasteride and higher doses of oral finasteride, the latter two being 5-α reductase inhibitors, Aditya K. Gupta, MD, PhD, of Mediprobe Research Inc, in London, Ontario, Canada, and colleagues sought to compare data on the three agents.
They note that, although there have been recent comparisons between oral and topical minoxidil, “to our knowledge, no studies have determined the comparative effectiveness of these 2 [formulations] with that of local and systemic dutasteride and finasteride.”
For the meta-analysis, the authors identified 23 studies that met their criteria, involving patients whose mean age ranged from 22.8 to 41.8 years.
For the primary endpoint of greatest increases in total hair count at 24 weeks, the analysis showed that the 0.5 mg/d dose of dutasteride topped the list, with significantly greater efficacy than of 1 mg/d of finasteride (mean difference, 7.1 hairs per cm2).
The 0.5 mg/d dose of dutasteride also showed superior efficacy to that of oral minoxidil at 0.25 mg/d (mean difference, 23.7 hairs per cm2) and 5 mg/d (mean difference, 15.0 hairs per cm2) and 2% topical minoxidil (mean difference, 8.5 hairs per cm2).
For the secondary endpoint of the greatest increase in the number of terminal hairs at 24 weeks, the 5 mg/d dose of minoxidil had a significantly greater efficacy than the 0.25 mg/d dose of the drug, as well as than at 2% and 5% minoxidil doses. topical formulations.
Minoxidil 5 mg/d was also significantly more effective than finasteride 1 mg/d for terminal hair count at 24 weeks.
In the longer term results at 48 weeks, the greatest increase in total hair count at 48 weeks was seen with finasteride 5 mg/d, which was significantly more effective compared to topical 2% minoxidil.
And the greatest increase in terminal hair count at 48 weeks was seen with 1 mg/d oral finasteride, which was significantly more effective than 2% and 5% topical minoxidil.
Based on the results, the authors ranked the agents in descending order of effectiveness:
0.5mg/d of oral dutasteride
5mg/d of oral finasteride
5mg/d of oral minoxidil
1mg/d of oral finasteride
5% topical minoxidil
2% topical minoxidil
0.25 mg/d oral minoxidil
Commenting on the analysis in an accompanying editorial, Kathie P. Huang, MD, of the Department of Dermatology, Brigham and Women’s Hospital, Boston, Massachusetts, and Maryanne M. Senna, MD, of the Department of Dermatology, Massachusetts General Hospital, Boston , say the results, in general, are consistent with their experiments, noting that 2% minoxidil is not generally used in men.
They note that “although topical minoxidil is ranked higher than oral minoxidil at very low doses of 0.25 mg, our personal experience is that oral minoxidil at doses of 1.25 mg to 5 mg is far superior to the topical minoxidil for the treatment of AGA”.
Important Adverse Event Considerations
However, it is important to consider adverse event profiles, as well as patient comorbidities when selecting agents, say the editorial authors.
With 1mg of finasteride, for example, potential adverse effects include decreased libido, erectile dysfunction, decreased ejaculatory volume, reduced sperm count, testicular pain, depression, and gynecomastia, they note. .
And although finasteride appears to be associated with a decreased risk of prostate cancer, those who receive the drug and develop prostate cancer may be diagnosed with higher grade prostate cancer; however, this “could be related to tissue sampling artifact,” the editorial authors say.
Fewer publications have been published on the adverse effect profile of dutasteride, which in itself is concerning.
Overall, “As more and more direct-to-consumer companies address male AGA emerge, it is especially important that the potential risks of these drugs are clearly communicated to patients,” add- they.
Further comments on the analysis at Medscape Medical News, Antonella Tosti, MD, Fredric Brandt Professor of Dermatology and Cutaneous Surgery at the University of Miami Miller School of Medicine in Miami, Forida, said the study offers important insights — and caveats.
“I think it’s a very interesting study, but you have to consider what works for your patients,” she said.
Tosti noted that the 5mg dose of minoxidil is a concern in terms of side effects. “This dose is quite high and could conceivably cause hypertrichosis, which can be a concern for both men and women.”
She agrees that the lack of data on the side effects of dutasteride is also a concern, particularly in light of some of the known side effects with other agents.
“That’s why I don’t use it much in younger patients — because I’m afraid it could potentially affect their fertility,” Tosti said.
In general, Tosti says she finds a combination of agents works best, as many clinicians use.
“I find dutasteride (0.5 mg/d) plus oral minoxidil (1-2.5 mg/d) plus topical 5% minoxidil to be the best combination,” she said.
The authors and Tosti have disclosed no relevant financial relationship.
JAMA Derma. Published online February 2, 2022. Summary, Editorial
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