ABSTRACT
INTRODUCTION: SB11 was recently approved as a ranibizumab biosimilar by the US Food and Drug Administration (FDA) and the European Commission (EC) as a therapy for retinal vascular disorders under the brand name Byooviz™. This study was performed to assess the analytical similarity between SB11 and reference products from the European Union (EU-ranibizumab) and United States (US-ranibizumab). METHODS: A comprehensive structural, physicochemical, and biological characterization was performed utilizing state-of-the-art analytical methods. Comparisons included the following: primary structure related to amino acid sequence and post-translational modifications; higher order structure; product-related substances and purity/impurity including size and charge variants. In addition, biological characterization included a series of mechanism of action (MoA)-related bioassays such as vascular endothelial growth factor (VEGF)-A binding assay (VEGF-A 165 and its isoforms), cell-based VEGF-A 165 neutralization assay, and anti-proliferation assay using human umbilical vein endothelial cells (HUVEC). RESULTS: The amino acid sequence of SB11 was identical to that of reference products, and post-translational modification profiles and higher order structures of SB11 were shown to be indistinguishable from the reference products. Product-related size and charge variants and aggregates were also similar. Using a broad range of VEGF-related functional assays, we demonstrated that SB11 has similar biological properties to reference products in VEGF-A binding activities (VEGF-A 165 and isoforms (VEGF-A 110, VEGF-A 121, and VEGF-A 189)), VEGF-A 165 neutralization, and HUVEC anti-proliferation. Overall, SB11 exhibits high similarity compared to EU/US-ranibizumab. CONCLUSION: Based on the comprehensive analytical similarity assessment, SB11 is highly similar to the EU/US-ranibizumab with respect to structural, physicochemical, and biological properties.
ABSTRACT
A biosimilar product needs to demonstrate biosimilarity to the originator reference product, and the quality profile of the latter should be monitored throughout the period of the biosimilar's development to match the quality attributes of the 2 products that relate to efficacy and safety. For the development of a biosimilar version of trastuzumab, the reference product, Herceptin®, was extensively characterized for the main physicochemical and biologic properties by standard or state-of-the-art analytical methods, using multiple lots expiring between March 2015 and December 2019. For lots with expiry dates up to July 2018, a high degree of consistency was observed for all the tested properties. However, among the lots expiring in August 2018 or later, a downward drift was observed in %afucose (G0+G1+G2). Furthermore, the upward drift of %high mannose (M5+M6) was observed in the lots with expiry dates from June 2019 to December 2019. As a result, the combination of %afucose and %high mannose showed 2 marked drifts in the lots with expiry dates from August 2018 to December 2019, which was supported by the similar trend of biologic data, such as FcγRIIIa binding and antibody-dependent cell-mediated cytotoxicity (ADCC) activity. Considering that ADCC is one of the clinically relevant mechanisms of action for trastuzumab, the levels of %afucose and %high mannose should be tightly monitored as critical quality attributes for biosimilar development of trastuzumab.
