Vascular endothelial growth factor (VEGF) has been proven to increase how permeable blood vessels are in the eyes, causing them to leak. When new blood vessels form, these may also leak blood and other fluids, leading to vision loss and complications. Currently, certain ophthalmologic conditions such as diabetic retinopathy or wet age-related macular degeneration are treated with anti-VEGF therapies. However, not everybody is eligible for these treatments – and it can be difficult for patients, who would require multiple eye injections.

Biotechnology company REGENXBIO Inc. is working to overcome treatment burden and issues through co-developing ABBV-RGX-314 with AbbVie. As REGENXBIO explains, ABBV-RGX-314 is:

a novel, one-time subretinal treatment that includes the NAV® AAV8 vector containing a gene encoding for a monoclonal antibody fragment. The expressed protein is designed to neutralize vascular endothelial growth factor (VEGF) activity, modifying the pathway for formation of new leaky blood vessels and retinal fluid accumulation.

Study Data: Phase 2 ALTITUDE Trial

Reporting from Drugs.com shared that REGENXBIO shared positive data from the ongoing Phase 2 ALTITUDE study. Within the study, researchers are evaluating ABBV-RGX-314 as a potential therapeutic intervention for people with diabetic retinopathy without center-involved diabetic macular edema. Participants were split into three groups. The first received 2.5×1011 genomic copies per eye, while the second and third received 5×1011 genomic copies per eye.

After one year, researchers are reporting that:

• The treatment was relatively safe and well-tolerated. While serious adverse reactions did occur, these were not related to treatment.
• Adverse reactions that did relate to treatment included conjunctival hemorrhage, conjunctival hyperemia, intraocular inflammation, and episcleritis.
• Dose level two seemed most effective, reducing the risk of vision-threatening events by 89% and halting disease progression. It also improved vision in 70.8% of treated individuals.

What You Should Know: Diabetic Retinopathy

A complication of diabetes, diabetic retinopathy is an eye condition that causes vision loss and even blindness. It is the most common form of vision loss in people between ages 24-75. High levels of sugar from diabetes damage the retina and its blood vessels. As the vessels leak and/or bleed, vision worsens. Being pregnant, or having had diabetes for a longer time, both increase the risk of diabetic retinopathy. If you have diabetes, you should get checked for diabetic retinopathy at least once per year. Symptoms – which include blurry or fluctuating vision, dark streaks/spots in your vision, and blindness – do not appear until the condition has progressed. People with diabetic retinopathy may also experience complications like diabetic macular edema, retinal detachment, and neovascular glaucoma. Managing your diabetes can prevent this condition. If you already hav this condition and it has progressed, treatment cannot reverse damage but it can stop further damage.