Table 1.

Analytical similarity: quality attributes evaluated

Quality attributesMethods
Primary structure
  • Intact molecular weight

  • Amino acid sequence

  • Disulfide bonds

High-order structure
  • Secondary structure

  • Tertiary structure

  • Thermal stability

Glycosylation
  • Afucosylation

  • Galactosylation

  • High mannose

  • Sialylation

Drug product attributes
  • Protein content

  • Subvisible particles

  • Deliverable volume

  • Appearance, pH, and osmolality

Fab-mediated biological activities
  • Inhibition of human umbilical vein endothelial cell (HUVEC) proliferation

  • VEGFA binding

  • Binding kinetics for VEGFA isoforms (165, 121, and 111)

  • Binding specificity

Fc-mediated biological activities
  • FcRn

  • Fcg receptors [RIa, RIIa, RIIb, RIIIa (158V and 158F type), and RIIIb]

  • C1q

  • Antibody-dependent cellular cytotoxicity (ADCC)

  • Complement-dependent cytotoxicity (CDC)

Product-related species
  • Charge variants

    • Acidic

    • Main

    • Basic

  • Size variants

    • Dimers and high-molecular weight species (HMW)

    • Heavy-chain (HC) and light-chain (LC) fragments

Stability
  • Degradation profiles under accelerated and stress conditions