3D-printed Gabapentin-loaded Implants for Sustained Release: Leveraging 3D Printing and Hot Melt Extrusion (HME) for Customizable Drug Delivery

Pediatric neuropathy poses significant challenges in pain management due to the limited availability of approved pharmacological options. Gabapentin, commonly used for neuropathic pain, offers therapeutic potential but necessitates careful dosing due to its variable bioavailability. This study investigates the integration of Hot Melt Extrusion and Fused Deposition Modeling in the development of polycaprolactone-based implants for sustained release of Gabapentin. A preliminary screening using Vacuum Compression Molding optimized formulations for Hot Melt Extrusion, enhancing material efficiency and process streamlining. Filaments with a diameter of 1.75 mm were successfully extruded and used for 3D printing of Gabapentin implants. Several tests were undertaken to characterize the prepared filaments and implants. Energy-Dispersive X-ray spectroscopy confirmed the uniform distribution of Gabapentin within the implant matrix. Solid-state characterization techniques were employed to assess the compatibility of implant components and to verify the solid-state of Gabapentin within the implant structure. In vitro drug release studies were conducted. Filaments with varying drug loadings were examined, revealing that a 20% w/w drug loading achieved an optimal balance between rapid and sustained release. Additionally, implants with different infill densities were analyzed, demonstrating that varying infill densities allow control over the amount and percentage of drug released. The 100% infill density resulted in the most sustained release effect, achieving approximately 40% drug release by day 28. These findings underscore the feasibility of 3D printing for producing personalized implants, emphasizing the potential for tailored drug release profiles to meet specific needs of pediatric patients.