Evaluation of Methods Employed in Establishing Preclinical Similarity of Adalimumab Biosimilars

Adalimumab, marketed as Humira, is a fully humanized monoclonal antibody that blocks the activity of tumor necrosis factor-alpha and is used in treating several autoimmune disorders. As one of the top-grossing pharmaceuticals, its global sales surpassed $20 billion in 2023, leading to significant biosimilar development, with 10 products available by 2025. This review analyses published preclinical studies to assess the evaluation methods employed to establish biosimilarity between Humira and four key biosimilars: ABP501 (Amjevita), FKB327 (Hulio), MSB11022 (Idacio), and SB5 (Imraldi). Our comparative analysis reveals that primary structure, glycosylation profiles, Fc receptor binding affinity, and TNF-alpha neutralization potency are critical quality attributes essential for establishing biosimilarity. Notably, while all four biosimilars demonstrated comparable functional properties to the reference product, variations in glycosylation patterns presented distinct regulatory challenges. This review is a valuable resource for biopharmaceutical scientists engaged in biosimilar development, ultimately supporting advancing more accessible and affordable treatment options while ensuring adherence to stringent efficacy, safety, and quality standards of adalimumab biosimilars.