Response of warts in epidermodysplasia verruciformis to treatment with systemic and intralesional alpha interferon

The susceptibility of human papillomavirus infection to polyclonal human leukocyte interferon (IFN-alpha) has been evaluated in patients with epidermodysplasia verruciformis (EV), a disease with extensive chronic papillomavirus-induced warts. In a double-blind, placebo-controlled study with intralesional IFN-alpha, four of five IFN-alpha-treated warts regressed; none of the placebo-treated warts responded (p = 0.024). Three patients with EV were treated with systemic IFN-alpha for 4 weeks in an open study, achieving partial regression of warts in all three. In a double-blind, placebo-controlled study, warts in two children with EV regressed with systemic IFN-alpha while two who received placebo showed no improvement. The lesions recurred following cessation of therapy. At the completion of therapy with IFN-alpha, histologic normalization was accompanied by a 95% decrease in the number of viral antigen-containing cells in the warts (p less than 0.001). We conclude that warts in EV respond to systemic and intralesional IFN-alpha.