Aggregates Quantification of Biopharmaceuticals in a Wide Range of Sizes Using Orthogonal Methods

摘要

While the relation of protein aggregates in biopharmaceutical products to the immunogenicity after administration is not fully understood and thus remains elusive, protein aggregates have been considered to be a potential risk for biopharmaceuticals as the aggregates may elicit an immune response.1 In 2014, the Food and Drug Administration (FDA) issued a draft guidance on immunogenicity assessment of therapeutic protein products in which the necessity of careful consideration of protein aggregates was described.2 Particles contained in biopharmaceuticals including protein aggregates are classified into different categories based on several properties such as size, chemical composition and the ability of dissociation upon dilution.3 Classification of the aggregates according to the size has been frequently employed and therefore (Figure 1), in this article, methods for protein aggregates evaluation is introduced according to size classification. Protein aggregates range from tens of nanometers to hundreds of micrometers with different densities that generate the varies of refractive index. Particles included in biopharmaceuticals with the diameter from 100 nm to 100 urn are called subvisible particles (SVPs).4 SVPs have been extensively investigated during the last ten years with regards to impact on the immune system and analytical instruments for SVPs characterization has been developed. It is now widely recognized that protein aggregates should be quantified based on the size of aggregates and by using at least two orthogonal methods.