An approach to the treatment of vitiligo by khellin.

An anticipated effect of khellin, related to its chemical structure, in the photochemotherapy of amelanosis has been investigated. In a double-blind clinical study, khellin has been orally administered to 30 vitiligo patients for 4 months with subsequent exposure to natural sunlight. At the end of the trial period, 5 patients out of 30 (16.6%) repigmented 90-100%; 7 cases (23.3%) repigmented 50-60% of the vitiliginous areas treated; 11 (36.6%) repigmented 25% or less, and 7 subjects (23.3%) showed negative response. 30 control subjects failed to repigment at all. The achieved repigmentation was stable after drug cessation for a period of 1 year. These data add a previously unreported effect for the non-psoralen compound, khellin, in the therapy of vitiligo.