Twin-Screw Extrusionin Pharmaceutical Drug Delivery: Principles, Processing Parameters, Applications, and Regulatory Considerations

AbstractTranscending conventional amorphous solid dispersion fabrication, contemporary researchunderscores the efficacy of co-rotating twin-screw extrusion (TSE) for the continuousmechanochemical induction of multi-component solid-state architectures, specificallycocrystals and co-amorphous systems, which yield synergistic enhancements in apparentsolubility and kinetic physical stability for bio-pharmaceutically challenging activepharmaceutical ingredients (APIs). The integration of predictive computational modellingwith highly customized, modular screw configurations circumvents inherent thermodynamicstabilization barriers, effectively minimizing thermal and mechanical degradation pathwayswhile optimizing scalability and process control during continuous operations. Concurrently,the implementation of inline and online Process Analytical Technology (PAT) arraysfacilitates real-time, non-destructive monitoring to ensure that critical process parametersstrictly adhere to predetermined control spaces, while the architectural versatility of modularscrew elements permits the precise calibration of specific mechanical energy and thermalinputs to guarantee the spatial and chemical homogeneity of complex extrudates. Beyondthese foundational stabilization strategies, current pharmaceutical engineering efforts aredirected toward utilizing multi-manifold co-extrusion techniques and integrated, inlineinjection moulding to enable the monolithic fabrication of sophisticated macromoleculardelivery networks characterized by tailored, programmable dissolution kinetics. Ultimately,the inherent geometric and operational flexibility of modular twin-screw platforms allows forthe precise modulation of mass throughput, rheological behaviour, and geometric shaping,thereby simultaneously optimizing both macro-level manufacturing efficiency and the microlevel biopharmaceutical performance of next-generation, patient-centric dosage forms.