Beyond Carrier Design: Fabrication Method as the Hidden Driver of NSAID Nanomedicine Performance

Background/Objectives: Diclofenac (DCF) and other nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used for pain and inflammation management; however, their clinical significance is limited by poor aqueous solubility, short biological half-life, and dose-dependent gastrointestinal, renal, and cardiovascular adverse effects. Nanocarrier-based delivery systems have been extensively explored because they can enhance the apparent solubility of poorly water-soluble NSAIDs, provide controlled and sustained drug release, prolong systemic circulation, and improve drug localization at the site of action. By reducing peak plasma concentrations and off-target exposure, these systems may decrease dose-dependent gastrointestinal and systemic adverse effects while maintaining therapeutic efficacy. Most studies focus on optimizing formulation composition, while the manufacturing process is often treated as a secondary parameter. The research critically evaluates conventional and emerging fabrication methods for NSAID nanocarriers, using DCF as the principal reference compound, with emphasis on their impact on physicochemical characteristics, reproducibility, scalability, and translational potential. Methods: A structured literature search was performed in PubMed/MEDLINE, Scopus, and Web of Science (2015-2026, with emphasis on 2022-2026) for DCF and NSAID-loaded submicron delivery systems reporting quantitative formulation data and clearly defined fabrication methods, resulting in a narrative review of approximately 375-395 eligible studies, comprising 75 DCF-specific studies and approximately 300-320 studies involving other NSAIDs that were included as representative surrogate systems when DCF-specific evidence was unavailable for particular fabrication approaches. The review followed Scale for the Assessment of Narrative Review Articles (SANRA) recommendations. Studies were analyzed using a standardized seven-parameter framework including encapsulation efficiency, release profile, particle size control, polydispersity, scalability, reproducibility, and process complexity. Results: Batch-based techniques, such as thin-film hydration for chitosan-coated liposomal systems, consistently provide high encapsulation efficiency, sustained drug release, and good biocompatibility. However, these methods are often associated with batch-to-batch variability, operator dependence, and limited scalability. In contrast, continuous manufacturing approaches, including microfluidic mixing, nanostructured lipid carriers, and Quality-by-Design (QbD)-guided processes, demonstrate improved control over particle size distribution and polydispersity, enhanced reproducibility, and better scalability potential. Conclusions: Manufacturing methodology is an important determinant of DCF and NSAID nanocarrier performance alongside formulation composition. Continuous manufacturing approaches offer promising improvements in reproducibility, process control, and scalability, but current evidence remains uneven across different nanocarrier classes. Further standardized comparative studies are needed to support their broader translation into clinical applications.