What is the future of 3D printing technique (FDM) in community or hospital pharmacies for the production of oral solid dosage forms ?

Fused deposition modeling (FDM) is a popular three-dimensional printing technology known for its environmental friendliness, design flexibility, and user-friendly operation. It operates by extruding a filament through a heated nozzle, which deposits successive layers of material, solidifying onto a build plate based on a computer-generated design. Recently, the interest in applying fused deposition modeling in the pharmaceutical sector has been increased (1). A manufacturing step, hot-melt extrusion (HME), is involved for the production of drug-loaded filaments. The versatility and benefits of implementing fused deposition modeling in the pharmaceutical field (community and/or hospital pharmacies) to develop innovative oral solid dosage forms are investigated.

Firstly, the modification of the drug dissolution rate by 3D printing is studied. Low aqueous solubility drugs belonging to the second class of the Biopharmaceutics Classification System were examined. Indeed, case studies were conducted using model drugs having different therapeutic interests (2). First, the Itraconazole was used and different formulations and design were produced by FDM (3). We have demonstrated that the dissolution rate relied on infill density and polymers composition, altering surface-to-volume ratio and component distribution, respectively. Second, the cannabidiol (CBD) has been studied by HME coupled to FDM. The amorphization of the drug during the process lead to a significant increase of the dissolution speed which will ultimately influence in vivo bioavailability (4).
Secondly, 3D printing's interest in personalized medicine is investigated. Healthcare now emphasizes patient-centered care and individualized therapies, especially for vulnerable groups like children. As an example, adrenal insufficiency treatment with hydrocortisone was selected. The few marketed oral hydrocortisone products lack suitability for various required doses. Moreover, compounding capsules often fail to meet mass and content uniformity standards. Hence, high-quality oral solid dosage forms with low hydrocortisone content were developed. Using the same filament but varying printed shapes dimensions, forms containing different drug doses were achieved. Two designs were created: an immediate release pediatric-friendly red mini-waffle shape (5) and a sustained release torus shape (6). Despite the considerable challenge of low drug doses, both printed forms met European Pharmacopeia specifications for mass uniformity, content uniformity, friability, and hardness.

FDM 3D printing technique is highly promising to develop low-dose and high-dose oral solid dosage forms thanks to the modification of printed forms shapes and sizes. This technology could be implemented in hospital and community pharmacies to produce drug products of advanced quality providing access to individualized healthcare for patients.