Efficacy of diphenylcyclopropenone in alopecia areata: a comparison of two treatment regimens

Introduction
Alopecia areata (AA) is a skin disease of unclear etiology. In AA, topical immunotherapy with diphenylcyclopropenone (DPCP) is considered the most effective treatment; however, the most common therapies give unsatisfactory results.

Aim
To assess the efficacy of a topical application of a solution of DPCP based on the intensity, duration and number of exacerbations of AA and to compare the efficacy of two treatment regimens.

Material and Methods
In this prospective study, 39 patients with AA were enrolled. Group A was treated at weekly intervals and group B at 3-week intervals. Hair loss was assessed by independent dermatologists and documented by photography and dermoscopy.

Results
After 6 months’ therapy, hair regrowth greater than 50% was observed in 21 patients, while worsening, no regrowth, or regrowth of less than 50% was seen in 18 patients. Regrowth exceeding 50% of initial loss was observed in 12 of 17 patients with baseline hair loss < 50%, in 9 of 22 patients with severe alopecia, and in 4 of 9 patients with alopecia totalis. Both groups showed significant improvement with higher efficacy in group B (54%) than group A (46%).

Conclusions
Treatment at longer intervals may be safer and more comfortable for patients; however, further research is required.