Selective Laser Sintering 3D Printing of Drug-Loaded Intravitreal Implants

Abstract

Frequent intravitreal injections are the standard treatment for chronic retinal diseases, but they are costly and inconvenient and carry potential complications. Intravitreal implants have emerged as an alternative approach capable of delivering sustained drug levels over extended periods. However, current implant manufacturing techniques, predominantly extrusion-based, present limitations when processing labile drugs. In this study, biodegradable implants are introduced, fabricated via selective laser sintering (SLS) 3D printing to achieve extended, controlled release of dexamethasone and riboflavin. By adjusting laser scanning speeds, diverse release profiles over 7 months are generated, after which the implant matrix fully degrades in the release medium. SEM-EDX and Raman spectroscopy confirmed uniform drug distribution in the implant, while XRPD, FTIR, and DSC analyses indicated that the drugs remained stable postmanufacturing. Additionally, investigations with ARPE-19 retinal cell cultures demonstrated excellent cytocompatibility of the implant. Overall, the findings confirm that SLS 3D printing is a promising approach for manufacturing intravitreal implants. This technique not only offers compatibility with a wide range of pharmaceutical compounds but also enables the tailoring of drug release by controlling the porosity of the implant. Consequently, SLS-based implants may improve patient outcomes by reducing injection frequency and associated complications.