Development and Evaluation of 3D-Printed Losartan Potassium Tablets Using Semi-Solid Extrusion: The Effect of Geometry, Drug Loading and Superdisintegrant.

Background/Objectives: Semi-solid extrusion (SSE) three-dimensional (3D) printing offers a versatile approach for fabricating personalized oral dosage forms. This study aimed to develop and optimize losartan potassium tablets produced via SSE 3D printing, focusing on the effects of polymer composition, tablet geometry, drug loading, and superdisintegrant concentration on printability and performance characteristics. Methods: Formulations containing hydroxypropyl methylcellulose (HPMC) 4500 at various concentrations were evaluated for suitability in an ethanol-water (9:1 v/v) solvent system. The optimized formulation (5% w/w HPMC 4500) was used to print tablets with varying shapes, drug loadings (5-15% w/w; approximately 50-150 mg losartan potassium per tablet), and croscarmellose sodium concentrations (0-3% w/w). Printed tablets were characterized for dimensional accuracy, mass uniformity, disintegration time, and drug release behavior. Drug release kinetics were modeled to elucidate the release mechanism. Results: All SSE-printed tablets exhibited excellent dimensional precision (SD < 0.8 mm) and mass uniformity (SD < 0.12 g). Increasing drug loading enhanced the initial release rate, reaching up to 63% in 45 min for 15% loading. The addition of 1% croscarmellose sodium reduced disintegration time to approximately 25 min. Drug release profiles were best described by the Korsmeyer-Peppas model (R2 > 0.96), indicating diffusion-controlled release. Conclusions: SSE 3D printing demonstrated robustness and flexibility in producing losartan potassium tablets with consistent quality, tunable release properties, and strong potential for personalized pharmaceutical manufacturing.