Williams R L
Office of Generic Drugs, Food and Drug Administration, Rockville, Maryland 20855.
Int J Dermatol. 1992 Oct;31 Suppl 1:2-5. doi: 10.1111/j.1365-4362.1992.tb04004.x.
After reviewing the history of generic drug substitution policy in the United States, this paper discusses issues of equivalence as they apply to topical drug products. Documentation of bioequivalence of topical products has been problematic, and current methods are being re-evaluated by the Food and Drug Administration. The FDA is currently evaluating various extensions of the basic methodology of the Stoughton-McKenzie vasoconstrictor assay, in order to develop a more comprehensive pharmacodynamic methodology for documenting topical drug bioequivalence. A modern pharmacodynamic model is described, based on nonlinear dose-response relationship, a baseline effect, and a maximum or plateau effect. The Agency's goal is a bioequivalent methodology that will be simple, readily performed, and based on more objective methods of measuring the vasoconstrictor response.
在回顾了美国仿制药替代政策的历史之后，本文讨论了适用于局部用药品的等效性问题。局部用产品生物等效性的文件记录一直存在问题，美国食品药品监督管理局正在对现行方法进行重新评估。美国食品药品监督管理局目前正在评估斯托顿 - 麦肯齐血管收缩试验基本方法的各种扩展，以便开发一种更全面的药效学方法来记录局部用药物的生物等效性。本文描述了一种基于非线性剂量反应关系、基线效应以及最大或平台效应的现代药效学模型。该机构的目标是建立一种生物等效性方法，该方法将简单易行，并基于更客观的测量血管收缩反应的方法。
