Dispositivo de liberação intravítrea para tratamento de degeneração macular relacionada à idade

• Autor(a) principal: Guerra, Maria Carolina Andrade
• Data de Publicação: 2023
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/12794
• topic: Degeneração macular relacionada à idade; Bevacizumabe; Nanofibras; Nanotecnologia; Implante biodegradável; Aplicação intravítrea; Age-related macular degeneration; Bevacizumab; Nanofibers; Nanotechnology; Biodegradable implant; Intravitreal application; OUTROS

Age-related macular degeneration, AMD, is a chronic eye disease which damages the macular area. It is the main cause of adult blindness worldwide. The pharmacological treatment of choice for the neovascular form of AMD consists of intravitreal injections of anti-VEGF agents that, occasionally, might be combined with corticosteroids. Intravitreal injections are the preferred route for drug delivery to the posterior segment of the eye but have limited therapeutic success due to the quick elimination of substances, requiring frequent injections that bring complications to the patient and low adherence to treatment. Intravitreal implants are capable to maintain therapeutic levels of drugs for a long period. Biodegradable nanofibers can modulate drug release in addition to allowing the incorporation of fragile bioactive substances. The present work aimed the development of biodegradable intravitreal implants containing dexamethasone coated with polymeric nanofibers containing bevacizumab as a therapeutic proposal for the treatment of AMD. Nanocoated implants were successfully developed. The characterization of the system, the study of degradation and efficiency of the coating process were evaluated by scanning electron microscopy. The drug release profile was determined by high performance liquid cromatography and the Bradford method. The antiangiogenic activity was determined by the chicken embryo chorioallantoic membrane model. The safety of the formulation was evaluated in rabbit eyes. So far, the system was successfully developed. The study degradation study confirmed the presence of nanofibers on the implant surface for up to 35 days. The degradation study demonstrated the presence of nanofibers on the surface of the implant for up to 35 days. The release profile showed that 68% of dexamethasone was released within 35 days and 90% of bevacizumab within 48 hours. The formulation presented activity in reducing vessels and was safe for the rabbits’ retina. No clinical or histopathological changes were observed, neither alteration in retinal thickness by optical coherence tomography during the 28 days. The developed implants, therefore, may be considered as a new alternative for the treatment of AMD.