Exploring tablet design options for tailoring drug release and dose via fused deposition modeling (FDM) 3D printing.

The aim of this paper was to explore tablet design options for FDM 3D printing for simultaneous tailoring of drug release and dose. The drug, griseofulvin (GF), the polymer, hydroxypropyl cellulose (HPC), and processing temperatures were selected to avoid confounding effects arising from drug-polymer interactions. Filaments containing 0-30 wt% GF were prepared using a twin-screw extruder. Five tablet designs were printed using combinations of fixed or varying drug-concentration filaments, fixed or varying tablet sizes, or placebo and drug-rich regions. Two of five options met the main objective; varying drug-concentration filaments for fixed tablet size or printing fixed size duo-tablet having internal placebo regions of varying sizes. Analysis of the drug dissolution profiles revealed that the tablet surface area to volume (SA/V) ratio was the dominant factor, a higher SA/V ratio resulted in a faster release rate, mostly independent of the drug amount or its placement within the tablet. Use of HPC led to near zero-order release for most cases. For duo-tablets, long lag times proportional to placebo shell-thickness were observed. These results suggest that design options other than varying the tablet size would be needed to achieve desired drug release from FDM-based 3D printed personalized dosages.