DPCP for the Treatment of Alopecia Areata

All subjects will be administered a sensitization dose of 0.05 mL 0.4% DPCP ointment formulation topically in the inner aspect of the upper right arm at Day -16, and 0.05 mL of four concentrations (0.1, .05, 0.01, 0.005%), prepared through dilutions in the ointment vehicle, topically on the inner aspect of the left thigh at Day -2. The weakest strength that may cause a minimal reaction (DTH skin reaction score of 1+) after two days will be chosen, and 0.75-1 g of that concentration will be applied to the scalp starting at Week 1 and administered subsequently twice a week for 18 weeks