DS-7080a, a Selective Anti-ROBO4 Antibody, Shows Anti-Angiogenic Efficacy with Distinctly Different Profiles from Anti-VEGF Agents

Purpose

Neovascular age-related macular degeneration (nAMD) results from choroidal neovascularization (CNV) and causes severe vision loss. Intravitreal anti-vascular endothelial growth factor (VEGF) therapies have significantly improved therapeutic outcomes; however, a substantial number of patients experience disease progression. Roundabout 4 (ROBO4) has been reported to be a vascular-specific protein that stabilizes vasculature in ocular pathological angiogenesis. To explore ROBO4 targeting as a novel treatment against neovascularization, we generated a humanized anti-human ROBO4 antibody, DS-7080a, and evaluated its efficacy.

Methods

ROBO4 mRNA in human whole eye cross-sections was examined by in situ hybridization. Human umbilical vein endothelial cell (HUVEC) migration was measured in the presence of VEGF, basic fibroblast growth factor (bFGF), hepatocyte growth factor (HGF), or conditioned medium of primary human retinal pigment epithelial (HRPE) cells. CNV was induced in cynomolgus monkeys by laser irradiation. Vascular leakage was measured by fluorescein angiography, and pathological changes were determined by histology.

Results

ROBO4 mRNA was detected in choroidal vessels of nAMD patients. DS-7080a suppressed HGF- or bFGF-induced HUVEC migration in addition to that induced by VEGF. Further, HUVEC migration induced by HRPE-conditioned medium was inhibited by either DS-7080a or ranibizumab in a similar manner, and the combination of these showed further inhibition. In a laser-induced CNV monkey model, single intravitreous administration of 1.1 mg/eye of DS-7080a reduced the incidence of grade 4 leakage from 44.45% in control eyes to 1.85% (P < 0.05 by Dunnett's test).

Conclusions

Anti-ROBO4 antibody DS-7080a suppressed HUVEC migration in a distinctly different fashion from anti-VEGF agents and improved laser-induced CNV in non-human primates.

Translational Relevance

DS-7080a may be a novel treatment option for nAMD.

The role of proteases and inflammatory molecules in triggering neovascular age-related macular degeneration: basic science to clinical relevance

Age-related macular degeneration (AMD) causes severe vision impairment in aged individuals. The health impact and cost of the disease will dramatically increase over the years, with the increase in the aging population. Currently, antivascular endothelial growth factor agents are routinely used for managing late-stage AMD, and recent data have shown that up to 15%-33% of patients do not respond to this treatment. Henceforth, there is a need to develop better treatment options. One avenue is to investigate the role proteases and inflammatory molecules might have in regulating and being regulated by vascular endothelial growth factor. Moreover, emerging data indicate that proteases and inflammatory molecules might be critical in the development and progression of AMD. This article reviews recent literature that investigates proteases and inflammatory molecules involved in the development of AMD. Gaining insights into the proteolytic and inflammatory pathways associated with the pathophysiology of AMD could enable the development of additional or alternative drug strategies for the treatment of AMD.

A centrifugal fluidic immunoassay for ocular diagnostics with an enzymatically hydrolyzed fluorogenic substrate

We present a novel "Lab-on-a-Disk" platform and demonstrate its capability for rapid and sensitive measurement of vascular endothelial growth factor (VEGF) intended for patients suffering from diabetic retinopathy (DR) and age-related macular degeneration (AMD). This approach combines sedimentation principles applied to microspheres under centrifugal force with signal amplification using an enzyme and a fluorogenic substrate for readout. The simple single channel per assay platform separates, washes and concentrates antibody-coated microspheres from excess label to produce a sensitive fluorogenic response proportional to the amount of VEGF in the sample. This platform has comparable sensitivity to conventional ELISA and can generate a readout within 16-18 min with no sample preparation beyond mixing assay reagents and loading on the disk. In the context of ocular diagnostics, this device has the potential to facilitate accurate dosing of anti-VEGF medications utilized to treat DR and AMD, as well as identify patients whose ocular VEGF levels are not elevated and who would therefore not benefit from standard anti-VEGF medications.

Angiogenesis-related biomarkers in patients with alcoholic liver disease: their association with liver disease complications and outcome

Angiogenesis is believed to be implicated in the pathogenesis of alcoholic liver disease (ALD). We aimed to explore the usefulness and accuracy of plasma angiogenic biomarkers for noninvasive evaluation of the severity of liver failure and ALD outcome. One hundred and forty-seven patients with ALD were prospectively enrolled and assessed based on their (1) gender, (2) age, (3) severity of liver dysfunction according to the Child-Turcotte-Pugh and MELD scores, and (4) the presence of ALD complications. Plasma levels of vascular endothelial growth factor (VEGF-A) and angiopoietins 1 and 2 (Ang1 and Ang2) were investigated using ELISAs. Multivariable logistic regression was applied in order to select independent predictors of advanced liver dysfunction and the disease complications. Significantly higher concentrations of Ang2 and VEGF-A in ALD patients as compared to controls were found. There was no difference in Ang1 levels in both groups. A positive correlation of Ang2 levels with INR (Rho 0.66; P < 0.0001) and its inverse correlation with plasma albumin levels (Rho –0.62; P < 0.0001) were found. High Ang2 concentrations turned out to be an independent predictor of severe liver dysfunction, as well as hepatic encephalopathy and renal impairment. Ang2 possessed the highest diagnostic and prognostic potential among three studied angiogenesis-related molecules.