A recombinant humanized monoclonal antibody (mAb) Eculizumab, C5-complement cascade inhibitor, is an important treatment of complement-based diseases recommended by international guidelines. Elizaria® Drug Product (DP), developed by IBC Generium, Russia, is the world's first registered biosimilar of eculizumab (Soliris®, Alexion Pharmaceuticals). Using sensitive state-of-the-art analytical techniques extensive similarity assessment has been conducted to demonstrate the structural and functional similarity of original Soliris® (Eculizumab Reference Product, RP) and the biosimilar Elizaria®, focusing on the physicochemical and biological quality attributes, including those known to affect the mechanisms of action. A multitude of analyses revealed that amino acid sequence is identical, the higher order structures, post-translational modifications, purity, and product variants are highly similar between Elizaria® DP and Eculizumab RP, except for minor differences in the relative abundance of the charge variants and glycan moieties considered not clinically significant. The results demonstrate that Elizaria® is highly analytically similar to Eculizumab RP in terms of physicochemical properties and biological activities.
