Development and evaluation of hot-melt–extruded diquafosol tetrasodium formulations for ophthalmic inserts: A design of experiments approach

This study aimed to develop, optimize, and evaluate hot-melt–extruded ophthalmic inserts capable of sustained release of diquafosol tetrasodium (DQS) via a design of experiments approach. DQS, a tear stimulant for dry eye management, faces challenges of frequent administration and low bioavailability. The developed insert uses biodegradable polymers in varied proportions to achieve sustained release. Optimized through mixture design, the insert completely dissolved within 24 h and maintained a stable drug content, thickness, and surface pH over three months at room temperature. In vitro corneal permeation studies on excised rabbit corneas demonstrated increased bioavailability, suggesting a reduced dosing frequency compared with conventional eye drops. Therefore, this insert has potential to enhance treatment outcomes by improving patient compliance and providing sustained drug effects.