Especially concerning children, the dosage of drugs should really be adjusted in small steps that match their quick growth. “If treating doctors calculate the needed dose, we can print the drug exactly as prescribed”, says Prof. Dr. Julian Quodback, former head of the project at the Institute of Pharmaceutics and Biopharmaceutics at HHU, and now professor at the university of Utrecht. The method is also suitable for precision medicine, where the dosage of active medical ingredients exactly matches individual patient needs. Batch sizes between one and several thousand pills are possible.
A team from the laboratory for manufacturing systems at TH Köln has developed a novel printing method for this. It is based on a hot-melt extruder, which melts and mixes polymers and active ingredients. This material is transported into the printing head and shaped into pills. One of the challenges: Hot-melt extrusion is carried out horizontally, but printing happens vertically. Therefore, the molten mass must be redirected. “The pharmaceutical materials that are used are very sensitive. We had to take care that redirection has no negative effect on the quality of the molten mass. Nevertheless, the technology used must be kept simple, as according to the requirements of the ‘Good Manufacturing Practice’ for pharmaceutical production systems, it needs to be easy to dismantle and clean after each extrusion process” says Haase. During the project, a prototype was created which was tested at HHU.
At the same time, the HHU pharmacists have studied the development of the printing materials. “The new technology has enabled us to consider a much broader spectrum of carrier materials and active substances. The reason is, that the gentle processing of the materials allows more sensitive active substances to be used in printing as well. It also becomes possible to use lipids, that is fats, as carrier materials. In this way, we again noticeably broaden the field of possible medically active ingredients, as there are many interesting candidates among these substances that cannot be processed as polymers”, says Arne Schulzen, PhD student at the Institute of Pharmaceutics and Biopharmaceutics at HHU. Other than using polymers and lipids, a next step is to test the printing of waxes in order to gain even more possibilities for manufacturing.