LAUSR

Background Despite regulatory advances, lack of age-appropriate formulations (AAFs) remains a challenge in paediatric practice. 3D-printing of oral dosage forms (ODFs) offers potential for AAFs for children. Optimising drug release from 3D-printed ODFs is an important technological step. Despite the abundant use of polyethylene oxides (PEOs) and their extensive use as an excipient, there have been no previous reports of applying this thermoplastic polymer species alone to fused deposition modelling (FDM) 3D printing. We assessed the impact of polymer molecular weight (MW) on the mechanical properties of the resultant filaments and their rheological properties. In the FDM 3D printing process, we also tested the effect of an innovative radiator-like design of the ODF on the acceleration of drug release patterns. Methods Blends of PEO (MW: 100K, 200K, 300K, 600K or 900K) with PEG 6K (plasticiser) and a model drug (theophylline) were prepared by hot-melt extrusion. The resultant filaments were used as a feed for a FDM 3D printer to fabricate innovative designs of ODFs in a radiator-like geometry with inter-connected paralleled plates and inter-plate spacing of either 0.5mm, 1mm, 1.5mm or 2mm. Results Varying blends of PEO and PEG allowed formation of mechanically resistant filaments (maximum load at break of 357, 608, 649, 882, 781 N for filament produced with 100K, 200K, 300K, 600K or 900K, respectively). Filaments of PEO at a MW of 200K-600K were compatible with FDM 3D printing. Further increase in PEO MW resulted in elevated shear viscosity (>104 Pa.S) at the printing temperature and hindered material flow during FDM 3D printing. A minimum spacing (1 mm) between parallel plates of the radiator-like design was essential to boost drug release from the structure. Conclusion These findings are essential in the development of next-generation personalised drug delivery doses using specialised polymer/polymer blends purposely optimised for FDM 3D printing. Disclosure(s) Nothing to disclose