Industrial Byproducts as Sustainable Feedstocks for Biopharmaceutical Manufacturing: Waste‐to‐Medicine Pathways for a Circular Economy

The escalating global demand for biopharmaceuticals is placing increasing strain on conventional production systems, highlighting the need for innovative and sustainable alternatives. Industrial byproducts, produced extensively across pharmaceutical and allied sectors, remain an underexploited resource with significant potential to reduce production costs and strengthen circular economy integration. This review systematically explores the sources and classification of industrial wastes relevant to biopharmaceutical manufacturing, while addressing critical regulatory, safety, and quality considerations for their adoption. Emerging biotechnological strategies-such as microbial fermentation, enzymatic biotransformation, and synthetic biology-driven metabolic engineering-are evaluated for their ability to convert industrial residues into high-value therapeutic products. Representative case studies demonstrate the feasibility of these approaches, including the utilization of agro-industrial waste for therapeutic enzymes, marine-derived residues for bioactive compounds, and fermentation byproducts for vaccine components. Environmental and economic implications are assessed through life cycle analysis (LCA) and cost-benefit evaluations, underscoring the alignment of waste valorization with sustainable manufacturing principles. Despite these opportunities, technological limitations, stringent quality and standardization requirements, and complex policy and ethical challenges remain substantial barriers. Future perspectives highlight the role of green bioprocessing, artificial intelligence (AI), and automation in optimizing waste-to-medicine pathways, alongside the long-term vision of achieving zero-waste biopharmaceutical production. By positioning industrial byproducts as valuable feedstocks, this review underscores their transformative potential in driving sustainable, resilient, and responsible healthcare manufacturing.