USE OF REFLECTANCE SPECTROPHOTOMETRY IN THE HUMAN CORTICOSTEROID SKINBLANCHING ASSAY

A reflectance spectrophotometric method for evaluation of the skin bla nching response to topical corticosteroids was evaluated. This blanchi ng response is used, for drug development and regulatory purposes, to assess potency and bioequivalence of topical corticosteroid products. The common method involves the use of a human rater to measure blanchi ng response in the skin. This study evaluated an instrumental alternat ive to the human rater and used this method to measure the differences between a number of brand name and generic topical corticosteroid pro ducts (six creams and six ointments). Products were applied to the for earms of normal volunteers and the blanching responses were assessed a fter 6 and 16 hours in both occluded and non-occluded skin sites. Only the fluocinolone acetonide generic and brand name preparations were d ifferent from each other. The spectrophotometric method proved to be e quivalent but not superior to the standard human observer method.