Given its limited systemic toxicity, , according to Sean Z. Wu, MD, of the department of dermatology, University of Cincinnati, and his associates.
In a retrospective study of 37 pediatric patients with AA, published in Pediatric Dermatology, Dr. Wu and his colleagues found that almost two-thirds experienced at least 50% regrowth of hair with topical anthralin treatment, but they described severe dermatitis and relapses as “potential drawbacks” of treatment.
The 37 patients were in the Cleveland Clinic AA areata database and began treatment with anthralin between 2004 and 2015, at aged 2-17 years (mean age 9). Over half (22) were females and most (31) were white. About 65% had patchy AA; the remainder had either alopecia totalis or alopecia universalis. Prior treatments included topical corticosteroids, minoxidil, and intralesional corticosteroids; four patients had not been treated previously. Patients were followed up from 51 days to more than 10 years, with a mean duration of 2.5 years. Treatment regimens, titrated up to achieve a mild to moderate dermatitis, included application of 0.5% cream for 5 minutes twice a week up to 1.0% cream for 30 minutes a day.
With topical anthralin, 12 (32%) of patients had complete scalp regrowth, 25 (68%) experienced at least 50% regrowth, and 5 (14%) had no response; in five patients, no follow-up information was available. Among those with at least 50% regrowth, the initial response was first noted at a mean of 3.4 months, and the mean time to maximal response was 15 months. This timeline suggests that treatment with anthralin should be continued beyond 1 year to ensure maximum beneficial results with hair regrowth, the authors wrote.
Factors associated with a positive response to treatment included less than 50% of scalp involvement. The two patients who used anthralin as monotherapy did not achieve a 50% scalp response, but the four treatment-naive patients were among those with at least 50% scalp regrowth, versus three of the five patients (60%) who had been treated previously with systemic steroids.
Two potential clinical limitations were noted during the study. Four patients had to stop treatment because of dermatitis, which suggests that patients and parents should be counseled about the potential for severe skin irritation with this treatment, the authors said. And among those who achieved at least 50% scalp regrowth, 16 of the 25 (64%) relapsed. The authors speculated that the effects of the drug could be temporary “or that the disease process may be able to overcome the anthralin effect over time.”
Dr. Wu and his coauthors cited the retrospective design and the small population size as major limitations of the study. Because some patients continued other treatments, it is “difficult to attribute scalp regrowth entirely to anthralin,” and variations in formulation and in treatment regimens are also factors to be considered, they cautioned. That AA has been found to spontaneously resolve, depending upon the severity of the disease, presents additional challenges for clinicians attempting to determine the extent to which anthralin offers therapeutic benefit, they pointed out.
In spite of the drug’s limitations, the authors concluded that the treatment was a safe and useful option as an “adjunct for those who fail first-line therapy with topical or intralesional corticosteroids.” They added that more work is needed to tailor treatment formulation, frequency, and duration to the specific needs of pediatric patients.
The authors had no relevant financial disclosures to report.
SOURCE: Wu SZ et al. Pediatr Dermatol. 2018;35:817-20.