Gene therapy for wet age-related macular degeneration
Wet age-related macular degeneration (AMD)
AMD is a common cause of vision loss. It affects an estimated 25 – 30 million people worldwide with the incidence expected to triple by 2025. The “wet” form of the condition accounts for 10 – 15% of all cases, and 90% of those with severe loss of vision.
OXB-203 is a gene-based treatment for neo-vascular wet AMD and potentially diabetic retinopathy. It aims to preserve and improve patients’ vision through anti-angiogenesis, the process of blocking the formation of new blood vessels. The product uses Oxford Biomedica’s LentiVector® technology to deliver two genes encoding the anti-angiogenic proteins endostatin and angiostatin. Following a single administration to the retina, OXB-203 creates genetically modified cells that produce the two proteins, preventing vascularisation.
Proof of concept
OXB-203 has demonstrated clear proof-of-concept in industry standard models of wet AMD. Results from a long-term Phase I clinical study show a positive safety profile up to four years post-treatment. The data also show a successful and sustained increase in endostatin and angiostatin expression and secretion, with dose escalation yielding a proportional increase in average expression.
Current standard treatments for wet AMD and other related ocular conditions achieved global sales of more than approximately US$7 billion. These require frequent repeated dosing, and as OXB-201 is designed as a single administration this would provide a significant market opportunity for the gene therapy.