Three-Dimensional-Printed Isoniazid Chewable Gels for On-Demand Latent Tuberculosis Treatment in Children

<b>Background/Objectives</b>: Pediatric drug administration is hindered by difficulties in swallowing conventional medications and the unpalatable taste of many drugs. Among diseases highlighting the need for improved pediatric delivery, tuberculosis (TB) stands out. One form of the disease is latent TB infection (LTBI), which is concerning in children. Effective LTBI treatment is crucial for prevention, with isoniazid (INH) widely used for its proven efficacy and safety. This study aims to develop innovative 3D-printed chewable gels containing INH for LTBI treatment. <b>Methods</b>: The gels were formulated using gelatin and carrageenan gum, sugar-free sweeteners, and flavoring. Two batches were prepared, and using 3D printing (3DP) with a semi-solid extrusion (SSE) module, chewable gels were produced. Rheological properties were measured to assess the feasibility of 3DP-SSE, evaluating the structural integrity and adequate fluidity of the formulation. The 3D-printed chewable gels were evaluated by visual, mass, and dimensional characteristics. In addition, the water activity, texture profile, INH and degradation product content, in vitro release, and taste-masking were investigated. <b>Results</b>: The optimized formulation maintained suitable rheological properties for 3DP-SSE, demonstrating consistent weight, dimensions, and stability after the process. The texture achieved a balance between printing parameters and shape maintenance, and the INH presented an immediate-release profile (>85% within 30 min). The chewable gels showed an improvement in palatability compared to conventional INH tablets. <b>Conclusions</b>: This innovative approach offers a promising solution for pediatric LTBI treatment, as it improves efficacy, medication acceptability, and on-demand access.