EVOLUTION OF THE BIOSIMILAR LANDSCAPE: A GLOBAL PERSPECTIVE

Abstract

Biosimilars have evolved from a European regulatory innovation into a major component of the global biological-medicine ecosystem. This narrative review examines that evolution through a science-to-regulation framework, moving beyond a descriptive catalogue of approvals to consider how analytical similarity, a stepwise evidence-development strategy, interchangeability policies, regulatory reliance, and market competition influence biosimilar development and access. The review compares the regulatory approaches of the World Health Organization (WHO), the United States Food and Drug Administration (FDA), the European Medicines Agency (EMA), and India. Particular attention is given to the increasing emphasis on sensitive orthogonal analytical methods, product-specific evidence requirements, reduction of unnecessary animal and clinical studies, post-marketing pharmacovigilance, and the distinction between scientific interchangeability and pharmacy-level substitution. The 2022 WHO guideline revision and India's 2025 revised Similar Biologics framework illustrate a broader international movement toward science-based flexibility, greater reliance on analytical and in-vitro evidence, and reduced duplication of studies. In the United States, the expanding biosimilar portfolio and evolution of interchangeability guidance demonstrate how regulatory experience can refine evidence requirements over time. The global landscape therefore appears to be shifting from an approval centred model toward a lifecycle model in which analytical characterization, manufacturing consistency, clinical confidence, pharmacovigilance, and market implementation are considered together. A harmonized but scientifically flexible approach may reduce development duplication while preserving standards for quality, safety, and efficacy.