A Double-blind, Randomized, Controlled Clinical Trial to Assess the Efficacy of a New Coal Tar Preparation (Exorex) in the Treatment of Chronic, Plaque-type PsoriasisSmith CH, Jackson K, Chinn S, Angus K, Baker JNWNClin Exp Dermatol. 2000;4:25:580-583
Exorex (Malvern, Pa) is a new topical formulation for the treatment of psoriasis, containing 1% coal tar with the addition of synthetic esterified essential fatty acids, similar to those identified in banana skins. The Exorex product has been classified by the United Kingdom Medicines Control Agency in the general sales list category, and the product is also available in the United States. The product was launched in 1998 in England and received a great deal of interest from the press and the public because of the banana skin content (although this was synthetic). Exorex was perceived to be a safe and effective preparation, without the adverse effects and limitations of conventional medicines. Yet no published controlled trial data could be found to substantiate claims in the promotional literature that the complex of esterified essential fatty acids offered a therapeutic and cosmetic advantage to the coal tar preparation alone. The objective of this double-blind, controlled, randomized right/left self-controlled trial was to compare Exorex against the same formulation without the essential fatty acid components for 8 weeks in 20 patients with chronic plaque psoriasis.