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1.
Drug Deliv Transl Res ; 6(6): 771-780, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27178165

RESUMO

Current administration of ranibizumab and other therapeutic macromolecules to the vitreous and retina carries ocular risks, a high patient treatment burden, and compliance barriers that can lead to suboptimal treatment. Here we introduce a device that produces sustained release of ranibizumab in the vitreous cavity over the course of several months. Composed of twin nanoporous polymer thin films surrounding a ranibizumab reservoir, these devices provide release of ranibizumab over 16 weeks in vitro and 12 weeks in vivo, without exhausting the initial drug payload. Following implantation in vivo, devices were well-tolerated and showed no sign of immune response. This platform presents a potential solution to the challenge of delivering protein therapeutics to the vitreous and retina for sustained periods of time.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Sistemas de Liberação de Medicamentos , Ranibizumab/administração & dosagem , Corpo Vítreo/metabolismo , Inibidores da Angiogênese/química , Animais , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Liberação Controlada de Fármacos , Feminino , Fluoresceína-5-Isotiocianato/administração & dosagem , Fluoresceína-5-Isotiocianato/química , Microscopia Eletrônica de Varredura , Nanoporos/ultraestrutura , Poliésteres , Coelhos , Ranibizumab/química
2.
Ophthalmic Surg Lasers Imaging Retina ; 47(3): 224-31, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26985795

RESUMO

BACKGROUND AND OBJECTIVE: To study the relationship between baseline morphologic characteristics of the choroidal neovascular (CNV) lesion and long-term development of macular atrophy in eyes with neovascular age-related macular degeneration (AMD) treated with ranibizumab (Lucentis; Genentech, South San Francisco, CA). PATIENTS AND METHODS: Certified graders evaluated baseline and 7-year follow-up (SEVEN-UP study) images of 41 eyes from the MARINA/ANCHOR and HORIZON trials. Using GRADOR software and stepwise linear regression, graders correlated lesion characteristics on fluorescein angiography (FA) at both visits with areas of definite decreased autofluorescence (DDAF) on fundus autofluorescence (FAF) imaging at the SEVEN-UP visit. RESULTS: Three of 41 eyes (7.3%) had macular atrophy on FA at baseline (mean ± standard deviation [SD] size: 0.29 mm(2) ± 1.50 mm(2)), 29 (70.7%) at SEVEN-UP (mean ± standard deviation [SD] area: 7.42 mm(2) ± 7.97 mm(2)). On FAF imaging at the SEVEN-UP visit, all 41 eyes (100%) had DDAF (mean ± SD size: 10.29 mm(2) ± 8.07 mm(2)). Variables significantly associated with area of DDAF at the SEVEN-UP visit were the area of leaking CNV lesion components (coefficient: 0.953; P < .001), the area of other lesion components (coefficient: 1.094; P = .038), and the area of retinal pigment epithelial (RPE) atrophy (coefficient: 1.334; P = .040) on baseline FA imaging. CONCLUSION: The area of DDAF at more than 7 years after initiation of ranibizumab therapy was 35% larger than the original CNV lesion. The baseline area of leaking CNV and other components of the CNV lesion and the baseline area of RPE atrophy were important predictors of the area of definite decreased autofluorescence, presumably corresponding to areas of photoreceptor and RPE loss. The findings from this study may guide hypothesis generation for future AMD trials.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Imagem Óptica , Ranibizumab/uso terapêutico , Doenças Retinianas/diagnóstico , Epitélio Pigmentado da Retina/patologia , Degeneração Macular Exsudativa/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Atrofia , Estudos de Coortes , Feminino , Angiofluoresceinografia , Seguimentos , Humanos , Injeções Intravítreas , Masculino , Tomografia de Coerência Óptica , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Degeneração Macular Exsudativa/diagnóstico
4.
Invest Ophthalmol Vis Sci ; 56(12): 7331-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26559479

RESUMO

PURPOSE: We created implantable intraocular devices capable of constant and continuous rapamycin release on the scale of months to years. METHODS: Polycaprolactone (PCL) thin films were used to encapsulate rapamycin to create implantable and biodegradable intraocular devices. Different film devices were studied by modifying the size, thickness, and porosity of the PCL films. RESULTS: In vitro release of rapamycin was observed to be constant (zero-order) through 14 weeks of study. Release rates were tunable by altering PCL film porosity and thickness. In vivo release of rapamycin was observed out through 16 weeks with concentrations in the retina-choroid in the therapeutic range. Rapamycin concentration in the blood was below the lower limit of quantification. The drug remaining in the device was chemically stable in vitro and in vivo, and was sufficient to last for upwards of 2 years of total release. The mechanism of release is related to the dissolution kinetics of crystalline rapamycin. CONCLUSIONS: Microporous PCL thin film devices demonstrate good ocular compatibility and the ability to release rapamycin locally to the eye over the course of many weeks.


Assuntos
Implantes Absorvíveis , Sistemas de Liberação de Medicamentos , Sirolimo/administração & dosagem , Uveíte/tratamento farmacológico , Animais , Segmento Anterior do Olho , Preparações de Ação Retardada/administração & dosagem , Modelos Animais de Doenças , Seguimentos , Imunossupressores/administração & dosagem , Coelhos , Fatores de Tempo
5.
Am J Ophthalmol ; 159(5): 915-24.e2, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25640411

RESUMO

PURPOSE: To assess the incidence and progression of macular atrophy and other key anatomic outcomes over 7 to 8 years in an early cohort of ranibizumab-treated exudative age-related macular degeneration patients. DESIGN: Follow-up analysis of long-term outcomes in a multicenter treatment cohort. METHODS: Fourteen study sites enrolled 65 previous subjects from the ranibizumab treatment arms of the ANCHOR, MARINA, and HORIZON trials. In a single update visit, clinical assessment and retinal imaging studies were performed, with comparison with each subject's prior results from the previous trials. Early Treatment Diabetic Retinopathy Study visual acuity was the primary outcome. Secondary outcomes, including area of macular atrophy and selected anatomic factors, were analyzed for associations with long-term vision outcomes. RESULTS: At a mean 7.3 years after ANCHOR or MARINA enrollment, mean visual acuity was 54 letters, study eyes having received a mean 1.6 injections per year since the HORIZON study. Macular atrophy was present in 98% of study eyes, the mean area increasing from 0.83 ± 0.96 mm(2) at the ANCHOR or MARINA year 2 exit to 2.22 ± 1.6 mm(2) at the SEVEN-UP visit, a growth rate of 0.28 mm(2)/year. Progression of macular atrophy was associated significantly with visual decline over this 5-year period (P < .001), and final macular atrophy lesion size was related significantly to final vision (P < .001). Other key anatomic outcomes (macular thickening, thinning, or fluid and submacular fibrosis) did not have significant effects on vision outcomes. CONCLUSIONS: Seven years after initiation of intensive ranibizumab therapy for exudative age-related macular degeneration, macular atrophy progression and severity were the primary anatomic determinants of visual outcomes.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Atrofia Geográfica/diagnóstico , Acuidade Visual/fisiologia , Degeneração Macular Exsudativa/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/uso terapêutico , Progressão da Doença , Feminino , Angiofluoresceinografia , Seguimentos , Atrofia Geográfica/fisiopatologia , Humanos , Incidência , Injeções Intravítreas , Masculino , Pessoa de Meia-Idade , Ranibizumab , Estudos Retrospectivos , Tomografia de Coerência Óptica , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Degeneração Macular Exsudativa/diagnóstico , Degeneração Macular Exsudativa/fisiopatologia
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