scholarly journals A Fully Human Monoclonal Antibody Targeting cKIT Is a Potent Inhibitor of Pathological Choroidal Neovascularization in Mice

Pharmaceutics ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1308
Author(s):  
Songyi Seo ◽  
Koung Li Kim ◽  
Yeongju Yeo ◽  
Ryul-I Kim ◽  
Hayoung Jeong ◽  
...  

Stem cell factor (SCF) and its receptor, cKIT, are novel regulators of pathological neovascularization in the eye, which suggests that inhibition of SCF/cKIT signaling may be a novel pharmacological strategy for treating neovascular age-related macular degeneration (AMD). This study evaluated the therapeutic potential of a newly developed fully human monoclonal antibody targeting cKIT, NN2101, in a murine model of neovascular AMD. In hypoxic human endothelial cells, NN2101 substantially inhibited the SCF-induced increase in angiogenesis and activation of the cKIT signaling pathway. In a murine model of neovascular AMD, intravitreal injection of NN2101 substantially inhibited the SCF/cKIT-mediated choroidal neovascularization (CNV), with efficacy comparable to aflibercept, a vascular endothelial growth factor inhibitor. A combined intravitreal injection of NN2101 and aflibercept resulted in an additive therapeutic effect on CNV. NN2101 neither caused ocular toxicity nor interfered with the early retinal vascular development in mice. Ocular pharmacokinetic analysis in rabbits indicated that NN2101 demonstrated a pharmacokinetic profile suitable for intravitreal injection. These findings provide the first evidence of the potential use of the anti-cKIT blocking antibody, NN2101, as an alternative or additive therapeutic for the treatment of neovascular AMD.

2017 ◽  
Vol 28 (2) ◽  
pp. 216-224 ◽  
Author(s):  
Alessandro Invernizzi ◽  
Aniruddha Agarwal ◽  
Maura Di Nicola ◽  
Fabio Franzetti ◽  
Giovanni Staurenghi ◽  
...  

Purpose: Intraocular tuberculosis (IOTB) can be complicated by choroidal neovascularization (CNV). However, when the CNV development is not accompanied by clear signs of inflammation, the etiology can be missed, especially in countries nonendemic for tuberculosis. We describe the clinical and imaging features of CNVs presenting as the first sign of IOTB initially misdiagnosed as exudative age-related macular degeneration (AMD). Methods: A retrospective review of clinical and imaging data of patients initially misdiagnosed with neovascular AMD later diagnosed with inflammatory CNV secondary to IOTB at tertiary referral centers was conducted. Features of fundus photography, fluorescein angiography, indocyanine green angiography, and enhanced depth imaging optical coherence tomography were analyzed. Distinguishing features between neovascular AMD and IOTB-associated CNV were evaluated. Results: Five patients over 55 years of age, erroneously diagnosed with exudative AMD, were included in the study. Multimodal imaging analysis allowed identification of peculiar choroidal alterations such as choroidal granulomas or choroiditis suggestive for posterior uveitis. Systemic workup for granulomatous uveitis including immunologic investigations such as tuberculin skin test or QuantiFERON TB Gold® and radiologic investigations revealed tubercular etiology in all the cases, allowing correct diagnosis and management of the uveitis and related CNV. Conclusions: Choroidal neovascularization represents a rare and unusual presenting sign of IOTB that can be misleading especially when it occurs in the elderly living in countries with low prevalence of the disease. Multimodal imaging can be helpful and should be employed, especially in atypical cases of CNV, in order to avoid misdiagnosis and/or diagnostic delays.


2009 ◽  
Vol 28 (1) ◽  
pp. 5-16 ◽  
Author(s):  
Pauline L. Martin ◽  
Paul E. Miller ◽  
Marielena Mata ◽  
Brian J. Christian

Angiogenesis is a major component of the pathogenesis of various ocular diseases, including age-related macular degeneration (AMD). CNTO95 is a fully human monoclonal antibody against αν integrins that has shown antiangiogenic properties in cynomolgus macaques and rats. Because angiogenesis inhibitors may have the potential to treat AMD, a proof-of-concept study was conducted in a macaque model of laser-induced choroidal neovascularization. In the course of this study, transient, intense anterior chamber ocular inflammation was observed within 24 hours following the first intravitreal or intravenous administration of the human monoclonal antibody. These animals had no outward signs of ocular toxicity or discomfort. Additional ocular safety studies demonstrated that the inflammation following intravenous administration of CNTO95 was not due to a contaminant in the vehicle, not due to endotoxin, and not a nonspecific reaction in the macaques from administration of a human monoclonal antibody. The anterior chamber ocular inflammation noted following the first dose did not recur with subsequent CNTO95 dosing. In repeated-dose toxicology studies, histopathological examination of the eyes revealed no ocular toxicity. The reason for the ocular inflammation following intravenous dosing remains unresolved but may be a secondary manifestation of a first-dose systemic infusion reaction.


2016 ◽  
Vol 9 (3) ◽  
pp. 69-76
Author(s):  
Nanuli V Ivanova ◽  
Oleg G Rasin ◽  
Aleksey V Savchenko ◽  
Olga A Litvinenko

Aim: To analyze the spontaneous reattachment of retinal pigment epithelium (RPE) after replacing the anti-VEGF drug - ranibizumab, with aflibercept in the treatment of neovascular AMD based on the example given in our clinical study. Material and methods. We carried out a retrospective analysis of the patient’s history with exudative detachment of RPE due to choroidal neovascularization in age-related macular degeneration. This patient was treated with anti-angiogenic treatment in the form of monthly IVI ranibizumab. At the time of treatment, the visual acuity of the left eye was 0.3 with sph + 1,5D = 0,5, in the fundus of the eye there was a high exudative detachment of RPE in the macular region common to the vascular arcades. The edges were determined by the detachment of the neuroepithelium and abundance of hard drusen. Using optical coherence tomography, (OCT) we saw that the center of the macula of the left eye had a high detachment of RPE, local detachment of the neuroepithelium at the edge of the RPE detachment and an abundance of hard drusen. The foveola was flattened, and beneath it, the RPE was detached in the center - thickness of 247 microns (m). After the seventh injection of ranibizumab, we used OCT to assess the condition of the retina. The retinas condition was almost the same as before. The thickness in the central zone was 251 m, detachment of neuroepithelium was not seen, the dome of the RPE detachment circuit was unchanged and visual acuity improved to 0.7 with a maximum correction. We then replaced ranibizumab with another anti-angiogenic drug - aflibercept. Results and discussion. Two weeks on from our control examination, we noticed there was a smooth bubble detachment of the RPE and a retinal prominence over the choroidal neovascular membrane area (CNM). The OCT scan indicated minimal RPE detachment, resorption of the exudate, presence of subretinal spindle - shaped formation near the temporal side (CNM? Scar?). Retinal thickness was 178 m at the fixation point. Intravitreal injections were stopped. Visual acuity increased to 0.8 and remained stable for 5 months, but there were signs of renewed activity of choroidal neovascularization. According to OCT, the thickness in the central parts of the retina increased to 230 m, there were intraretinal cysts and increased spindle - shaped formation under the RPE. After 10 months of IVI aflibercept, acute vision decreased to 0.5, the thickness at the point of fixing increased to 250 m, subretinal formation increased and oozing of fluid was observed mainly parafoveal, which explains the high visual acuity. We then administered IVI ranibizumab. Two weeks later, the retinal thickness was 169 m, visual acuity improved to 0.8, but 1 month later we found that the retinal thickness had increased once more and decreased to 0.7. After 3 months after IVI ranibizumab, retinal thickness at the fixation point reached 286 m and visual acuity dropped to 0.5. Conclusion. In our practice, we face patients with neovascular AMD, who respond badly to ranibizumab. For such patients, it is important to replace ranibizumab with a better, more therapeutically effective anti-VEGF drug with anti-vaso proliferative properties. Aflibercept is an effective substitute for ranibizumab which was shown in this clinical case.


The understanding of the pathogenesis of the development of choroidal neovascularization (CNV) in age-related macular degeneration (AMD) continues to evolve. Epidemiological, histopathological, and biochemical evidence indicates that neovascular AMD is associated with oxidative damage, lipofuscin accumulation, chronic inflammation, and mutation in the complement system. Molecular targets have been identified that serve as the basis for developing new, better treatments for neovascular AMD.


2021 ◽  
Vol 6 (6-1) ◽  
pp. 12-18
Author(s):  
M. A. Kovalevskaya ◽  
O. A. Pererva

Background. In economically developed countries, age-related macular degeneration (AMD) is the leading cause of visual disability among the population of the older age group. The main criterion for the anti-VEGF treatment of neovascular AMD is the activity of choroidal neovascularization (CNV), which is determined by its confi guration. The search for optimal criteria for quantifying the state of the macular region in order to decide on the appointment of anti-VEGF therapy continues.Aim: improving the effi ciency of diagnosis and treatment of AMD based on the assessment of the configuration of vascular system on the “Key to Diagnosis II” platform.Material and methods. The study included 341 patients: 64 % (218 patients, 267 eyes) with non-neovascular AMD, 36 % (123 patients, 174 eyes) – with neovascular AMD. 56 patients (58 eyes) had active type I CNV. Group 1A – active CNV before treatment (9 patients, 9 eyes), group 1B – non-active CNV after treatment with antiVEGF (9 patients, 9 eyes); control group – 10 patients (10 eyes) without AMD. Analysis of OCT-angio images of choriocapillaries included the isolation of CNV, its area, fractal dimension (Df) and the complexity of the vascular system (CVS) counting.Results. Group 1A: Df – 1.5871 ± 0.05, CVS – 2.29 ± 0.29, area – 11734 ± 4866; group 1B: Df – 1.6462 ± 0.08, CVS – 1.65 ± 0.18, area – 6797 ± 3818; control: Df – 1.9167 ± 0.06, CVS – 1, area – 0. Significant differences were found for CVS (p = 0.0003). Df correlates with the CNV area (p = 0.7) and is probably an unreliable parameter due to incomplete visualization of active CNV.Conclusions. CVS is a quantitative biomarker for determining the activity of type 1 CNV in patients with AMD and can serve as a parameter for convolutional neural networks training for automated analysis of OCT angiography images based on the “Key to Diagnosis II” platform


2021 ◽  
pp. 3-13
Author(s):  
Mona Abdelkader ◽  
Ayman Fawzy ◽  
Wael El-doskey

Purpose: To study the effects of intra-vitreal injection of ranibizumab on pattern electroretinogram (PERG) and multifocal electroretinogram(MF-ERG) parameters in choroidal neovascularization and to test the retinal toxicity of ranibizumab. Method: Fifty eyes of 50 patients with subfoveal choroidal neovascularization were included in the study. Thirty (30) eyes had neovascular age related macular degeneration (nAMD) and 20 eyes had myopic choroidal neovascularization. Ranibizumab was injected intravitreal monthly for3 months. Optical Coherence Tomography Angiography (OCT) was performed at the initial and final visits. Visual acuity, Pattern and multifocal electroretinography (PERG, MFERG) were performed before and at 1,2,3,6 months after intravitreal injection. Results: There was no clinical significant reduction of parameters of either MFERG or PERG after intravitreal injection of ranibizumab. There was significant increase in visual acuity, decrease in central macular thickness ,decrease in total macular volume and improvement in the parameters of both PERG and MFERG after intravitreal injection. Conclusion: Intravitreal injection of ranibizumab is effective in treatment CNV and safe. It has no retinal toxicity since no reduction in PERG& MFERG parameters. Keywords: AMD; Ranibizumab; PERG; MFERG


2021 ◽  
Vol 15 ◽  
Author(s):  
Juhee Kim ◽  
Jong-Heon Kim ◽  
Ji Yeon Do ◽  
Jung Yi Lee ◽  
Ryoji Yanai ◽  
...  

Age-related macular degeneration (AMD), especially neovascular AMD with choroidal neovascularization (CNV), is the leading cause of blindness in the elderly. Although matrix metalloproteinases (MMPs) are involved in pathological ocular angiogenesis, including CNV, the cellular origin of MMPs in AMD remains unknown. The present study investigated the role of microglial MMPs in CNV. MMP activities were analyzed by gelatin zymography in aqueous humor samples from patients with CNV and laser-induced CNV mice. Active MMP-9 was increased in the aqueous humor samples from neovascular AMD patients compared with control subjects. In the retinal pigment epithelium (RPE)/choroid from CNV mice, active MMP-9 increased, beginning 1 h post-CNV induction, and remained upregulated until Day 7. In RPE/choroid from CNV mice, active MMP-9 was suppressed by minocycline, a known microglial inhibitor, at 6 h and 1-day post-CNV induction. Flow cytometry revealed that the proportion of activated microglia increased very early, beginning at 1 h post-CNV induction, and was maintained until Day 7. Similarly, immunohistochemistry revealed increased microglial activation and MMP-9 expression on CNV lesions at 6 h and 1-day post-CNV induction. SB-3CT, an MMP inhibitor, decreased vascular leakage and lesion size in laser-induced CNV mice. These findings indicated nearly immediate recruitment of activated microglia and very early MMP-9 activation in the RPE/choroid. The present study newly identified a potential role for early microglial MMP-9 expression in CNV, and furthermore that modulating microglial MMP expression is a novel putative therapeutic for CNV.


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