Biopharmaceuticals and Biosimilars from Molecule to Market: An Integrative Review of Comparability, Immunogenicity, Interchangeability, and Access

Biopharmaceuticals have transformed treatment across oncology, immunology, and other therapeutic fields, but their molecular heterogeneity, manufacturing dependence, immunogenic potential, and cost complicate development and access. Biosimilars seek to expand competition without reproducing an originator’s proprietary manufacturing process or exact molecular microheterogeneity. This integrative review examines how evidence from manufacturing knowledge, analytical and functional comparability, co