Agata Grzejdziak, Zofia Mazurkiewicz, Agnieszka Dużyk, Katarzyna Sikora, Witold Jamróz, Mateusz Kurek

Current advancements in hot-melt extrusion of filaments as intermediates in the 3D drug printing process using the fused deposition modeling method
2024-07-25

Object of review. The hot-melt extrusion (HME) technology is widely used in various industries, including the pharmaceutical industry, as a method of incorporating a drug substance into a polymer matrix, but also, especially in recent years, as a method of producing filaments used in three-dimensional (3D) printing. Hot-melt extrusion, together with fused deposition modeling (FDM) printing, are the most rapidly developing technologies in 3D printing of medicinal products. However, published scientific papers primarily focus on the printing process, with filament extrusion often constituting only a small portion of the work. Nevertheless, the quality of the filaments determines both the success of the FDM printing process and the future of this technology. It is anticipated that drug printing may find application primarily in the manufacturing of small batches of medicinal products or in hospital and community pharmacies. In some countries, such as Spain and Finland, some attempts are already underway to apply 3D printing technology in hospital pharmacy settings. However, in order for the FDM method to find its place in the preparation of personalized medicines, it is required to ensure the quality and safety of the products prepared by this method.

Goal of the review. The aim of this paper is to review the current research achievements, requirements, and advancements in hot-melt extrusion of the filaments and to indicate directions for further development of this technology. Filaments must possess certain mechanical, thermal, and physicochemical properties to ensure the stability and quality of the final drug product. Despite the significant advances that have taken place in recent years, there is a need to standardize test methods and quality requirements for filaments, which is crucial for their application to the 3D printing of drugs.

Material and methods. We analyzed the most recent, carefully chosen literature, primarily from the past five years, that describes current advancements in hot-melt extrusion of pharmaceutical filaments, their testing methods, and quality requirements.

Results. The article describes the properties that the filaments used in FDM should have, methods for their evaluation, and selected studies on the stability and suitability of filaments in drug manufacturing. The article also highlights the need for standardized testing methods, given the discrepancies in the methodology across the described research.

Conclusions. The study’s findings indicate that using hot-melt extrusion to produce filaments and 3D printing can be an effective method for producing personalized drug forms tailored to individual patients’ needs while ensuring the quality of the key intermediate product, which is the filament containing the drug substance.

Keywords: hot-melt extrusion, 3D printing, polymers, filament.

© Farm Pol, 2024, 80(3): 147–156