title: Characterization and comparison of commercially available TNF receptor 2-Fc fusion protein products.
abstract: Because of rapidly increasing market demand and rising cost pressure, the innovator of etanercept (Enbrel®) will inevitably face competition from biosimilar versions of the product. In this study, to elucidate the differences between the reference etanercept and its biosimilars, we characterized and compared the quality attributes of two commercially available, biosimilar TNF receptor 2-Fc fusion protein products. Biosimilar 1 showed high similarity to Enbrel® in critical quality attributes including peptide mapping, intact mass, charge variant, purity, glycosylation and bioactivity. In contrast, the intact mass and MS/MS analysis of biosimilar 2 revealed a mass difference indicative of a two amino acid residue variance in the heavy chain (Fc) sequences. Comprehensive glycosylation profiling confirmed that biosimilar 2 has significantly low sialylated N-oligosaccharides. Biosimilar 2 also displayed significant differences in charge attributes compared with the reference product. Interestingly, biosimilar 2 exhibited similar affinity and bioactivity levels compared with the reference product despite the obvious difference in primary structure and partial physiochemical properties. For a biosimilar development program, comparative analytical data can influence decisions about the type and amount of animal and clinical data needed to demonstrate biosimilarity. Because of the limited clinical experience with biosimilars at the time of their approval, a thorough knowledge surrounding biosimilars and a case-by-case approach are needed to ensure the appropriate use of these products.
authors.affiliation: International Joint Cancer Institute and College of Pharmacy, Second Military Medical University, Shanghai, China.
authors.forename: Qingqiao
authors.initials: Q
authors.lastname: Tan
authors.forename: Qingcheng
authors.initials: Q
authors.lastname: Guo
authors.forename: Chen
authors.initials: C
authors.lastname: Fang
authors.forename: Chong
authors.initials: C
authors.lastname: Wang
authors.forename: Bohua
authors.initials: B
authors.lastname: Li
authors.forename: Hao
authors.initials: H
authors.lastname: Wang
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.forename: Yajun
authors.initials: Y
authors.lastname: Guo
mesh_terms: D000818:Animals; D000915:Antibody Affinity; D059451:Biosimilar Pharmaceuticals / Q000494:pharmacology*; D002460:Cell Line; D000068800:Etanercept; D005060:Europe; D005347:Fibroblasts / Q000276:immunology*; D006031:Glycosylation; D006801:Humans; D007141:Immunoglobulin Fc Fragments / Q000235:genetics; D007074:Immunoglobulin G / Q000494:pharmacology*; D051379:Mice; D018124:Receptors, Tumor Necrosis Factor; D047889:Receptors, Tumor Necrosis Factor, Type II / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism* / Q000493:pharmacokinetics; D013810:Therapeutic Equivalency
chemical_list: D059451:Biosimilar Pharmaceuticals; D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D018124:Receptors, Tumor Necrosis Factor; D047889:Receptors, Tumor Necrosis Factor, Type II; D011993:Recombinant Fusion Proteins; D000068800:Etanercept