Purpose <p>Biosimilars offer a cost-effective alternative to originator biologics, but their global adoption remains uneven due to differences in regulatory standards, pharmacovigilance capacity, and healthcare infrastructure. This review compares biosimilar regulatory and safety frameworks in developed (United States, European Union, Japan) and developing (India, Brazil, South Africa) markets to identify key gaps and opportunities for alignment.</p> Methods <p>A focused narrative review was conducted using peer-reviewed literature from PubMed, Scopus, and Web of Science complemented by official regulatory guidelines, pharmacovigilance reports, and policy documents published by national and international health authorities.</p> Results <p>Regulatory agencies in developed economies like FDA, EMA, and PMDA maintain rigorous evaluation processes and robust pharmacovigilance systems. In contrast, developing economies exhibit variability: India, while a major biosimilar producer, faces quality and harmonization challenges; Brazil and South Africa struggle with affordability and infrastructure, limiting uptake.</p> Conclusion <p>The successful integration of biosimilars depends on regulatory maturity, strong pharmacovigilance, and stakeholder awareness. Efforts should focus on harmonizing international standards, strengthening safety monitoring, and improving clinician and patient education. Key takeaways include the need for shared international safety data platforms, the elimination of redundant local bridging studies, and the implementation of pharmacy-level substitution to maximize cost-savings. Harmonization is critical to ensuring equitable access to biologics across diverse economic landscapes.</p> Graphical Abstract <p></p>