Novel sustained release biodegradable drug delivery system for targeting chronic rhinosinusitis
Abstract
Chronic rhinosinusitis (CRS) is a condition in which the nasal cavity and the paranasal sinuses become inflammed causing facial pressure, pain, headache, nasal obstruction and thick nasal discharge. CRS severely affects patients’ quality of life and it can last for a duration greater than 12 weeks. Nasal sprays are most commonly used for this condition but the duration of action is short. In polypoidal form of CRS, sprays also fail to target the potentially infected anatomic sites. Functional endoscopic sinus surgery (FESS) is a treatment option for patients non-responsive to medical strategies. However, relapses related to infections and inflammations are often encountered setbacks following FESS. To overcome these limitations, sustained release biodegradable drug-eluting nasal implants were developed, which has the potential to be used as adjuncts to FESS to promote wound healing. Several formulations of dexamethasone-loaded poly (lactic-co-glycolic acid) (PLGA) based microparticles were developed using emulsification-solvent evaporation method. The in vitro drug release profiles, encapsulation/loading efficiency, surface morphology, mean particle size and size distribution profiles of the formulations were investigated. The results suggested that dexamethasone-loaded PLGA microparticles release the drug in a sustained manner for more than 3 months owing to slow degradation of PLGA. After optimization of suitable formulations, the microparticles were incorporated into an implant or delivery system (sponge and hydrogel). The entrapment efficiency and surface morphology of the implants were subsequently characterized.