According to research from the Biosimilars Council, $81 billion worth of brand name biologics will lose their patents by 2020. As a result, we are seeing a significant increase in the development of lower cost biosimilar alternatives, as well as more applications for FDA approval of biosimilars for expiring biologic drugs. In fact, this market is expected to grow more than 25-fold over the next five years. But because the structure of a biosimilar is unlikely to be identical to that of the reference product, developers must ensure there are no clinically meaningful differences in safety, purity, and potency between the reference product (originator) and the biosimilar, and that the biosimilar can be measured within the human body in a way that is highly similar to the original biologic drug after which it is modeled. Therefore, it is critical that robust pharmacokinetic (PK) assays be developed.
Regulatory agencies require biosimilar PK in support of nonclinical and clinical studies, but demonstrating the bioanalytical similarity and comparability between the biosimilar and the reference product via PK analysis is not an easy undertaking. The assay must be able to quantify the biosimilar and reference product within the assay range in a head-to-head manner. Therefore, the developed method must be properly validated to establish its reliability to consistently, accurately, and precisely measure the concentration of the biosimilar and reference product in the relevant biological matrix. Laboratories taking on this task need to have a complete understanding of the rigorous bioanalytical and regulatory demands of biosimilar PK, and have expert scientific support that is capable of meeting the inherent complexities with which it is associated.
Two fellow BioAgilytix scientists, Saara Mansouri and Jennifer Zemo, and I recently produced an article titled, “Meeting the Rigorous Demands of Biosimilar Pharmacokinetics.” The article discusses the important aspects of biosimilar pharmacokinetic assay development and validation, as well as the regulatory issues concerning biosimilar pharmacokinetics.