Clinical development and trial design of biosimilar products: a Japanese perspective.

In recent years, development of biosimilar products has attracted considerable attention. Because of the structural complexity of biologics, it is difficult to demonstrate that a biosimilar product is identical to the reference product. Therefore, for the development of biosimilar products, we need to adopt an approach that is different from generic product development. In this article, we discuss the guidelines for the development of biosimilar products along with the case examples of biosimilar product development in Japan. In addition, we discuss several issues of clinical trial design for demonstrating biosimilarity to a reference product.