title: Clinical trials of topical corticosteroids in psoriasis: correlations with the vasoconstrictor assay.
abstract: It would be desirable to develop an alternative system to clinical studies to evaluate the potency of generic topical corticosteroids and of new formulations of existing innovator corticosteroids. The vasoconstrictor assay is a reliable method for testing potency; however, its results do not always agree with clinical studies. Psoriasis offers an ideal clinical model to evaluate corticoid potency because the ability to perform within-patient comparisons of the treatment of bilateral lesions permits meaningful comparisons with a relatively small sample size. The results of bilateral comparisons in psoriasis agreed with those of the vasoconstrictor assay in 20 of 23 comparisons of active agents and in numerous comparisons of active corticosteroids with a placebo. Eczematous dermatoses do not lend themselves well to bilateral paired comparison studies and therefore require parallel treatment studies with relatively large sample sizes to produce statistically significant comparisons.
authors.affiliation: Department of Dermatology and Cutaneous Surgery, Scripps Clinic and Research Foundation, La Jolla, California 92037-1093.
authors.forename: R C
authors.initials: RC
authors.lastname: Cornell
mesh_terms: D000287:Administration, Topical; D000893:Anti-Inflammatory Agents / Q000493:pharmacokinetics / Q000494:pharmacology / Q000627:therapeutic use*; D001624:Betamethasone Valerate / Q000627:therapeutic use; D004311:Double-Blind Method; D005500:Follow-Up Studies; D006801:Humans; D006854:Hydrocortisone / Q000031:analogs & derivatives / Q000627:therapeutic use; D010919:Placebos; D011565:Psoriasis / Q000188:drug therapy* / Q000378:metabolism; D012867:Skin / Q000187:drug effects; D017443:Skin Diseases, Eczematous / Q000188:drug therapy; D013810:Therapeutic Equivalency; D014662:Vasoconstrictor Agents / Q000494:pharmacology
chemical_list: D000893:Anti-Inflammatory Agents; D010919:Placebos; D014662:Vasoconstrictor Agents; C038363:hydrocortisone valerate; D001624:Betamethasone Valerate; D006854:Hydrocortisone