Pharmaceutical Technology Department. Faculty of Pharmacy. University of the Basque Country. Vitoria. Spain.
Curr Pharm Biotechnol. 2009 Dec;10(8):772-4. doi: 10.2174/138920109789978702.
The prime difference between generics and biosimilars is that while generics contain the exact active ingredient as in the originator product, biosimilars are only "similar" and not "identical" to the originator biological medicine. This difference appears due to the nature of the biopharmaceutical medicines which are extremely complex to manufacture (it is not possible to make an exact copy of a biotech medicine in the same way as a traditional chemical molecule can be copied). In fact, it is widely accepted that for biopharmaceuticals, the "process is the product". Minor changes during the manufacturing process can have critical consequences in the patients. The vast majority of the biopharmaceuticals on the market are produced by genetic engineering using various recombinant expression systems. Most of the recombinant proteins that have been granted marketing approval to date are produced either in E. Coli or in recombinant mammalian cell lines. Several approaches may be undertaken to determine biopharmaceuticals potency. Bioassays represent the most relevant potency-determining assay, as they directly assess the biological activity of the product. These assays involve applying a known quantity of the substance to be analyzed to a biological system which responds to this applied stimulus. The response is measured quantitatively, allowing an activity value to be assigned to the substance being assayed.
仿制药和生物类似药的主要区别在于，虽然仿制药含有与原研产品完全相同的活性成分，但生物类似药与原研生物药物“相似”而非“相同”。这种差异源于生物制药的性质，其制造非常复杂（不可能像传统化学分子那样复制生物技术药物的精确副本）。事实上，人们普遍认为，对于生物制药来说，“工艺就是产品”。制造过程中的微小变化可能会对患者产生关键影响。目前市场上绝大多数生物制药都是通过基因工程使用各种重组表达系统生产的。迄今为止，获得批准上市的大多数重组蛋白要么在大肠杆菌中产生，要么在重组哺乳动物细胞系中产生。可以采用多种方法来确定生物制药的效力。生物测定法是最相关的效力测定法，因为它们直接评估产品的生物活性。这些测定法涉及将已知数量的待分析物质应用于对该应用刺激有反应的生物系统。通过定量测量响应，为正在进行测定的物质分配一个活性值。
