药物再定位或药物再利用是使某药针对原定用途之外的疾病,从而获取新增价值的一种策略。已面市或失败药物的再定位,为大中小型制药公司开启了一股新的收入来源,吸引了风险投资,预计2012年可产生200亿美元的年销售额[1]。药物再定位并不是个全新的策略,已经成功再定位的药物例子并不少见,如吉西他滨和西地那非(见表1)。这些例子及其他很多例子都解决了部分患者群体 Drug repositioning or drug reuse is a strategy that allows a drug to be added to a disease other than the intended use. The repositioning of already-available or failed drugs opens a new source of revenue for small, medium and large pharmaceutical companies, attracting venture capital and is expected to generate 20 billion U.S. dollars in annual sales by 2012 [1]. Drug relocation is not a completely new strategy, and examples of drugs that have been successfully repositioned are not uncommon, such as gemcitabine and sildenafil (see Table 1). These and many other examples address some of the patient population