BRAIN HEALTH ASSESSMENT IN MACULAR DEGENERATION PATIENTS UNDERGOING INTRAVITREAL ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR INJECTIONS (THE BHAM STUDY): An Interim Analysis

Suppression of matrigel-induced choroidal neovascularization by AAV delivery of a novel anti-Scg3 antibody

Efforts to develop gene therapy for long-term treatment of neovascular disease are hampered by ongoing concerns that biologics against vascular endothelial growth factor (VEGF) inhibit both physiological and pathological angiogenesis and are therefore at elevated risk of adverse side effects. A potential solution is to develop disease-targeted gene therapy. Secretogranin III (Scg3), a unique disease-restricted angiogenic factor described by our group, contributes significantly to ocular neovascular disease. We have shown that Scg3 blockade with a monoclonal antibody Fab fragment (Fab) stringently inhibits pathological angiogenesis without affecting healthy vessels. Here we tested the therapeutic efficacy of adeno-associated virus (AAV)-anti-Scg3Fab to block choroidal neovascularization (CNV) induced by subretinal injection of Matrigel in a mouse model. Intravitreal AAV-anti-Scg3Fab significantly reduced CNV and suppressed CNV-associated leukocyte infiltration and macrophage activation. The efficacy and anti-inflammatory effects were equivalent to those achieved by positive control AAV-aflibercept against VEGF. Efficacies of AAV-anti-Scg3Fab and AAV-aflibercept were sustained over 4 months post AAV delivery. The findings support development of AAV-anti-Scg3 as an alternative to AAV-anti-VEGF with equivalent efficacy and potentially safer mechanism of action.

Normal-Tension Glaucoma and Potential Clinical Links to Alzheimer's Disease

Glaucoma is a group of optic neuropathies and the world's leading cause of irreversible blindness. Normal-tension glaucoma (NTG) is a subtype of glaucoma that is characterized by a typical pattern of peripheral retinal loss, in which the patient's intraocular pressure (IOP) is considered within the normal range (<21 mmHg). Currently, the only targetable risk factor for glaucoma is lowering IOP, and patients with NTG continue to experience visual field loss after IOP-lowering treatments. This demonstrates the need for a better understanding of the pathogenesis of NTG and underlying mechanisms leading to neurodegeneration. Recent studies have found significant connections between NTG and cerebral manifestations, suggesting NTG as a neurodegenerative disease beyond the eye. Gaining a better understanding of NTG can potentially provide new Alzheimer's Disease diagnostics capabilities. This review identifies the epidemiology, current biomarkers, altered fluid dynamics, and cerebral and ocular manifestations to examine connections and discrepancies between the mechanisms of NTG and Alzheimer's Disease.

Brolucizumab for the treatment of diabetic macular edema

PURPOSE OF REVIEW

To review the available data supporting the use of brolucizumab in the treatment of diabetic macular edema (DME).

RECENT FINDINGS

Brolucizumab is a humanized single- chain variable antibody fragment (scFv), the smallest functional subunit of an antibody approved for intravitreal use. Three phase III studies demonstrate that at 52 weeks, brolucizumab has statistically superior anatomical outcomes of reducing retinal thickness (54.0-57.5% of brolucizumab treated eyes achieved central subfield thickness <280 μm compared to 40.1 - 41.4% of aflibercept treated eyes) and retinal fluid (present in 54.2-60.3% of brolucizumab treated eyes compared to 72.9-78.2% of aflibercept treated eyes). Brolucizumab also demonstrated a prolonged durability up to 16 weeks, thus reducing treatment burden. The visual outcomes appear noninferior to current anti-VEGF agents with an increased risk for intraocular inflammatory events (0.3-4.7% compared to 0.6-1.7%).

SUMMARY

Results from recent phase III trials showing the efficacy and safety of brolucizumab presents an additional therapeutic option in the DME treatment landscape. It can reduce treatment burden in DME with increased inter-treatment intervals while conferring efficacy in both functional and anatomical outcomes. Caution should be taken regarding the risks of intraocular inflammation, retinal vasculitis, and retinal vascular occlusion.

VEGF Paradoxically Reduces Cerebral Blood Flow in Alzheimer’s Disease Mice

Vascular dysfunction plays a critical role in the development of Alzheimer’s disease. Cerebral blood flow reductions of 10% to 25% present early in disease pathogenesis. Vascular Endothelial Growth Factor-A (VEGF-A) drives angiogenesis, which typically addresses blood flow reductions and global hypoxia. However, recent evidence suggests aberrant VEGF-A signaling in Alzheimer’s disease may undermine its physiological angiogenic function. Instead of improving cerebral blood flow, VEGF-A contributes to brain capillary stalls and blood flow reductions, likely accelerating cognitive decline. In this commentary, we explore the evidence for pathological VEGF signaling in Alzheimer’s disease, and discuss its implications for disease therapy.