BioPharmaSpec provides a complete solution for Etanercept/ Enbrel comparability, biosimilarity and characterization studies.

Etanercept (trade name Enbrel) is a recombinant protein made by fusing the TNF-receptor and the constant region of the IgG1 antibody. It is a large biopharmaceutical with a molecular weight of 150 kDa that, similar to Humira, Simponi and Remicade, inhibits tumor necrosis factor alpha (TNFα). TNFα is central to the inflammatory response and plays a major role in inflammatory/ autoimmune diseases such as arthritis, plaque psoriasis and ankylosing spondylitis. Etanercept is therefore used to treat certain inflammatory diseases.

Biosimilar Characterization Considerations

The guidelines state that Etanercept/ Enbrel comparability and characterization should include determination of physicochemical and structural properties, purity, impurities and quantity in line with ICH Topic Q6B:

Structural Characterization

Physicochemical Characterization

Functional Testing by Custom Biologics

  • Caspase 3/Apoptosis Assay
  • NFkB Reporter Assay
  • TNFα Neutralization Assay
  • Antibody-Dependent Cell Cytotoxicity (ADCC) Reporter Bioassay
  • Complement-Dependent Cytotoxicity (CDC) Assay
  • Proliferation Assays
  • Binding Assays
    • ELISA
    • BLI

Product Specific Technical Considerations

Particular attention should be paid to the Post Translational Modifications (PTMs) including:

  1. Disulfide bridges (particularly in the TNFα region)
  2. C-terminal Lysine
  3. Glycosylation (in particular, levels of galactosylation, fucosylation and sialylation, N-glycosylation site profiling and occupancy and O-glycosylation structure and site occupancy).
  4. Deamidation
  5. Oxidation