GENE therapy company Oxford Biomedica has received approval from US regulators to test its eye disease treatment on 18 patients.

The company, based at Oxford Science Park, uses an equine virus to deliver genes to the retina in the hope of repairing damage from age-related macular degeneration, a major cause of blindness.

The treatment, called RetinoStat, was designed using the company's patented LentiVector gene-delivery technology, and is one of four treatments being developed in partnership with pharmaceutical giant Sanofi-aventis.

The trial at the Wilmer Eye Institute at Johns Hopkins, Baltimore, led by Prof Peter Campochiaro, will evaluate three dose levels and assess safety, aspects of visual acuity and ocular physiology. It is hoped to start by the end of December.

Age-related macular degeneration is a major cause of blindness affecting an estimated 25 to 30 million people worldwide and is expected to triple by 2025.

RetinoStat aims to preserve and improve the vision of patients through blocking the formation of new blood vessels. Lab tests suggests patients will only need a single dose, while current treatments often require frequent, repeated administration.

Chief executive John Dawson said: “This is a significant milestone for Oxford BioMedica and is a result of the outstanding effort from our research and development and regulatory teams."

It is the first US clinical study to directly administer this type of treatment to patients, and he said the approval boosted hopes for the company's Parkinson’s disease product, ProSavin.

He added: "Together with our partner, Sanofi-aventis, we look forward to progressing all four of our gene-based ocular products into clinical development by the end of 2011.”

The loss-making company, an Oxford University spin-out, had £13.7m cash at the end of September, compared with £16.3m in June. Its hopes are pinned on meeting development milestones triggering payments from its commercial partners over the next 12-18 months.