120 Efficacy of imiquimod in the treatment of alopecia areata

*Chantal Bolduc, **Harvey Lui , **David McLean, **Jerry Shapiro *University of Montreal, Montreal, Québec, **University of British Columbia, Vancouver, British Columbia

Alopecia areata (AA) is a relatively common, non-scarring type of hair loss. The pathophysiology of alopecia areata is still unclear, but an autoimmune mechanism is the most widely accepted theory. Based on current available data, AA appears to exhibit a TH1 cytokine profile. IL-1 has been found to be associated with alopecia areata, and is a potent inhibitor of hair growth in vitro. Furthermore IL-1 appears to induce histologic changes similar to those seen in alopecia areata. Imiquimod (Aldara) is a topical immune response modifier that stimulates the secretion of different cytokines, most of which are associated with a TH1 response. Although AA is potentially associated with IL-1 and a TH1 cytokine profile, imiquimod, which most likely enhances TH1 response, has been used anecdotally for alopecia areata with some success. The aim of this pilot study was to assess the potential efficacy of imiquimod in the treatment of alopecia areata. The study had a prospective, open-label, left-right half-head controlled design. Only half the scalp was treated 3 times a week for 4 months, while the other side was left untreated. Hair loss was graded semiquantitatively and photographs were taken at baseline and serially every 4 weeks throughout the study. The treatment was very well tolerated. Six patients with extensive AA (40-99%) were included in the study. One patient experienced bilateral regrowth. One patient worsened on both treated and non treated sides. His condition was active when he entered the study and his course was most likely unrelated to imiquimod. The other four patients did not grow hair and kept a similar score from baseline to the end. In conclusion, this pilot study shows that imiquimod applied 3 times/week is unlikely to have efficacy in severe AA.