Dual-Phase Ocular Insert with Bromfenac-Loaded PLGA MPs in a PVA Matrix for Sustained Postoperative Anti-Inflammatory...

Background: Postoperative ocular inflammation is a frequent complication of eye surgeries commonly managed using corticosteroids or nonsteroidal anti-inflammatory drug (NSAIDs) eye drops. However, poor ocular bioavailability and patient non-adherence due to frequent dosing limit the therapeutic efficacy of conventional eye drops. This study aimed to develop a sustained-release ocular insert containing bromfenac sodium (BS)-loaded poly(lactic-co-glycolic acid) (PLGA) microparticles (MPs) with an initial 3% (w/w) free BS fraction incorporated into a poly(vinyl alcohol) (PVA) matrix designed to achieve a dual-phase release profile for improved postoperative therapy. Methods: PLGA-based MPs were fabricated using a double emulsion solvent evaporation technique and incorporated into PVA films to produce ocular inserts with varying MP content. Formulations were characterized for morphology, particle size, zeta potential, drug loading, entrapment efficiency, mucoadhesion, drug distribution, and in vitro release. Data were analyzed by an ANOVA and t-tests with p < 0.05 as significance. Results: MPs were smooth, spherical, and well-dispersed in the PVA inserts. Particle sizes ranged from 3.7 to 5.6 µm, with drug loading 7-8% and entrapment efficiencies 47-52%. Multiphoton imaging confirmed uniform drug distribution. In vitro release showed a dual-phase profile with an initial burst followed by sustained release for up to 4 days, with only negligible further release through Day 6 in one formulation (M1-7525). Conclusions: The developed BS-loaded PLGA MP/PVA insert demonstrated a dual-phase release profile relevant to postoperative ocular inflammation. Its biodegradable, single-application design holds promise for enhancing compliance and therapeutic outcomes in ophthalmic care.