Direct powder extrusion 3D printing: Fabrication of drug products using a novel single-step process

Three-dimensional (3D) printing is revolutionising how we envision manufacturing in the pharmaceutical field. Here, we report for the first time the use of direct powder extrusion 3D printing: a novel single-step printing process for the production of printlets (3D printed tablets) directly from powdered materials. This new 3D printing technology was used to prepare amorphous solid dispersions of itraconazole using four different grades of hydroxypropylcellulose (HPC - UL, SSL, SL and L). All of the printlets showed good mechanical and physical characteristics and no drug degradation. The printlets showed sustained drug release characteristics, with drug concentrations higher than the solubility of the drug itself. The printlets prepared with the ultra-low molecular grade (HPC - UL) showed faster drug release compared with the other HPC grades, attributed to the fact that itraconazole was found in a higher percentage as an amorphous solid dispersion. This work demonstrates the potential of this innovate technology to overcome one of the major disadvantages of fused deposition modelling (FDM) 3D printing by avoiding the need for preparation of filaments by hot melt extrusion (HME). This novel single-step technology could revolutionise the preparation of amorphous solid dispersions as final formulations and it may be especially suited for preclinical studies, where the quantity of drugs is limited and without the need of using traditional HME.