Stability Studies in Prefilled Syringe Systems

Abstract

Prefilled syringe (PFS) systems are the fastest-growing primary container for biologic drugs (monoclonal antibodies, vaccines, peptides), with the global market exceeding USD 7 billion and projected 10% annual growth. Unlike vials, PFS store drug product in direct contact with the container throughout its shelf life (typically 18-36 months), creating unique stability challenges: protein adsorption to syringe surfaces, silicone oil-induced protein aggregation, tungsten-mediated oxidation from needle-staking residues, leachables from rubber plunger stoppers, and mechanical stress from transport vibration. Regulatory agencies (FDA, EMA) require comprehensive stability data demonstrating that the drug-device combination maintains potency, purity, and safety throughout its shelf life under recommended and stress conditions. We present the Prefilled Syringe Stability Assessment Framework (PSSAF), evaluating five stability assessment approaches-- accelerated degradation modelling, container-closure interaction profiling, computational protein-surface simulation, high-throughput forced degradation screening, and predictive shelf-life AI -- across four PFS material systems (glass barrel with silicone oil, cyclic olefin polymer barrel, ceramic-coated glass, and silicone oil-free systems). Our PFS Stability Score (PFSS) measures degradation prediction accuracy, interaction characterisation completeness, shelf-life prediction reliability, regulatory data package adequacy, and development time efficiency. Predictive shelf-life AI achieves the highest PFSS (0.924) through machine learning models trained on 15,000 historical stability datasets that predict 36-month stability outcomes from 3-month accelerated data, while container-closure interaction profiling achieves the highest characterisation completeness (0.960) through systematic identification of all drug-device interaction pathways.