Clinical programs in the development of similar biotherapeutic products: rationale and general principles.

Similar biotherapeutic products (SBPs) or biosimilars are biologics developed by pharmaceutical manufacturers to match originator biologics that have been on the market for a long time and lost their exclusivity (patent and market protection). The recently issued WHO guidelines on evaluation of SBPs provide clear guidance for manufacturers and regulators on how to develop and gain approval for these products. The present contribution illustrates the rationale for and general principles of the clinical programs used in the development of SBPs, taking the example of the three biosimilar products developed and marketed in Europe by Sandoz, namely growth hormone (Omnitrope®, the first ever EU biosimilar approval), erythropoietin α (Binocrit®), and filgrastim (Zarzio®).