The 5-alpha reductase inhibitor (5-ARI) dutasteride (Avodart) likely is the most efficacious among the three drugs currently used to treat androgenetic alopecia (AGA), or male pattern baldness, according to a network meta-analysis.
Overall rank for efficacy across the four endpoints of change in total and terminal (the longer, thicker strands on the head) hair counts after 24 and 48 weeks of treatment favored 5 mg/day of oral dutasteride, followed by:
- 5 mg/day of oral finasteride (Propecia)
- 5 mg/day of oral minoxidil (Rogaine)
- 1 mg/day of oral finasteride
- 5% topical minoxidil
- 2% topical minoxidil
- 0.25 mg/day oral minoxidil
"The robustness of this order could be confirmed by results from future randomized clinical trials," Aditya Gupta, MD, PhD, of Mediprobe Research in London, Ontario, and colleagues reported in .
"As efficacy data from head-to-head trials accumulate, there could be a better sense of the relative efficacy of the different doses of the 5-ARIs and minoxidil," the authors suggested.
Dutasteride at 0.5 mg/day might be the most efficacious treatment for AGA because its half-life is 5 weeks compared to only 6 hours for finasteride, they said.
While dutasteride and oral minoxidil are often used off-label for male hair loss, finasteride is approved by the FDA for the treatment of AGA, as are both topical formulations of minoxidil.
Which option is best is a common question for patients, and these results should help physicians and patients make more informed choices, Kathie Huang, MD, Brigham and Women's Hospital, and Maryanne Senna, MD, of Massachusetts General Hospital, both in Boston, pointed out in an accompanying .
While the study results won't surprise many clinicians, they noted, physicians must remember that each of the three drugs used to treat AGA have adverse events, some serious.
Sexual dysfunction and depression have been associated with finasteride. High-dose oral minoxidil in turn is also associated with a risk of pericardial effusion and cardiac tamponade, with a black box warning from the FDA.
Furthermore, although dutasteride appeared to have the greatest benefit out of the three AGA drugs evaluated, "the adverse event profile is not as well studied as that for finasteride, 1 mg, and patients should be counseled regarding the adverse event profile being not well studied," Huang and Senna wrote.
"Patients and physicians have different thresholds for risk in terms of adverse events, even when the frequency is low, as they may adversely affect quality of life," the editorialists added. "As more direct-to-consumer companies treating male AGA emerge, it is especially important that the potential risks of these medications be made clear to patients."
In the meta-analysis, all 23 studies -- 21 of which were randomized controlled trials -- investigated monotherapy with any dose and any route of administration of the three drugs evaluated.
The mean age of the cohort ranged from 22.8 to 41.8 years. The four endpoints were quantified in hairs/cm2.
For change in total hair count at 24 weeks, the greatest increase was seen with 0.5 mg/day of dutasteride. The difference in hairs/cm2 was:
- 23.7 vs minoxidil at 0.25 mg/day
- 15 vs minoxidil at 0.5 mg/day
- 8.5 vs the 2% solution of minoxidil
- 7.1 vs finasteride at 1 mg/day
Increase in terminal hair count at 24 weeks showed that minoxidil at 5 mg/day was perhaps, not unexpectedly, significantly more efficacious than the lower 0.25 mg/day dose, with a mean difference in favor of the higher dose of 43.6 hairs/cm2. The same pattern held true for its topical forms in both concentrations of 2% and 5%.
Minoxidil at 5 mg/day also significantly bested 1 mg/day of finasteride.
At 48 weeks, the greatest increase in total hair count was seen with 5 mg/day of finasteride, followed by 1 mg/day of finasteride, and 2% topical minoxidil, where the mean difference between higher-dose finasteride and topical minoxidil was 20.7 hairs/cm2. However, oral minoxidil and dutasteride had no results available for this endpoint, as investigators pointed out.
Available results on terminal hair count at 48 weeks handed the advantage to 1-mg/day finasteride versus topical minoxidil, with a mean difference of 32.1 hairs/cm2 for the 2% formulation and 26.2 hairs/cm2 for the 5% formulation. The other drugs didn't have study data.
As the authors pointed out, there were no exclusion criteria for participants' race and ethnicity, so findings may not be generalizable for all races and ethnicities.
Huang and Senna also pointed out that the study highlights the paucity of therapeutic options for the treatment of male pattern baldness and suggested that it is time to explore other ways of treating AGA to help improve quality of life for men with this problem.
Disclosures
Gupta and coauthors reported having no relevant relationships with industry.
Huang disclosed relationships with Concert, Pfizer, Incyte, and Aclaris, as well as patent/royalty/intellectual property interests.
Senna disclosed relationships with Follica, Lilly, Pfizer, Arena Pharma, and Deciphera.
Primary Source
JAMA Dermatology
Gupta AK, et al "Relative efficacy of minoxidil and the 5-α reductase inhibitors in androgenetic alopecia treatment of male patients. A network meta-analysis" JAMA Dermatol 2022; DOI: 10.1001/jamadermatol.2021.5743.
Secondary Source
JAMA Dermatology
Huang KP, Senna MM "Hair are the rankings -- 5-α reductase inhibitors and minoxidil in male androgenetic alopecia" JAMA Dermatol 2022; DOI: 10.1001/jamadermatol.2021.5625.