Key considerations in the preclinical development of biosimilars

• Preclinical data for the development of biosimilars are different from those obtained in the development of the reference biologic.
• The principles and processes for demonstrating biosimilarity involve a stepwise process of comparing the proposed biosimilar with its reference biologic product.
• The goal of biosimilar development is to match the proposed biosimilar quality target product profile (QTPP) to that of the reference biologic product.
• It is hoped that biosimilars will help increase therapeutic options and patient access to important biologics for the treatment of various diseases, ranging from rheumatoid arthritis to cancer.

Biosimilar development requires several steps: selection of an appropriate reference biologic, understanding the key molecular attributes of that reference biologic and development of a manufacturing process to match these attributes of the reference biologic product. The European Medicines Agency (EMA) and the FDA guidance documents state that, in lieu of conducting extensive preclinical and clinical studies typically required for approval of novel biologics, biosimilars must undergo a rigorous similarity evaluation. The aim of this article is to increase understanding of the preclinical development and evaluation process for biosimilars, as required by the regulatory agencies, that precedes the clinical testing of biosimilars in humans.