Navigating the complexity of biologics and biosimilar: structural, clinical, and regulatory insights
Biologics are complex therapeutic agents derived from living cells, and biosimilar is their highly similar, lower-cost alternatives developed after patent expiration. These therapies have revolutionized treatment paradigms in oncology, immunology, and rare diseases by providing targeted and effective interventions. Despite their potential, challenges persist, including high production costs, complex biomanufacturing processes, regulatory inconsistencies, and concerns about environmental sustainability. Early research on biosimilar often focused narrowly on efficacy or cost-effectiveness, overlooking broader functional implications, immunogenicity risks, and sustainability of large-scale manufacturing. Limited comparative studies between originator biologics and biosimilar created significant knowledge gaps in defining critical quality attributes and establishing robust benefit–risk profiles. Furthermore, while recombinant protein-based therapeutics and monoclonal antibodies dominate the biopharmaceutical market, their development and clinical integration are hindered by multifaceted challenges, including regulatory heterogeneity, quality assurance, and long-term patient safety considerations. Early literature has also inadequately addressed process design innovations, sustainable manufacturing practices, and the complexities of clinical adoption in diverse healthcare systems. These lacunas necessitate a comprehensive review that integrates structural, functional, clinical, and regulatory perspectives, with a particular emphasis on immunogenicity and sustainability. This article aims to bridge these gaps by offering a critical appraisal of biosimilar development, adoption, and clinical integration, informing future strategies and policy frameworks.
Nagarajan B, Anandbabu T, Vasudevan E, Lakshmi K, Grace DC, Prabha KS. Navigating the complexity of biologics and biosimilar: structural, clinical, and regulatory insights. J App Biol Biotech 2025. Article in Press. http://doi.org/10.7324/JABB.2026.274436
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