Single jab could prevent millions from going blind

As Briton is first to get gene therapy...

SURGEONS are hoping to halt the most common cause of blindness with a pioneering injection of gene therapy.

A British woman is the first to undergo the treatment – which may only need a single jab to be effective.

The team from Oxford University has spent the last 12 years experimenting with gene therapies to slow or stop the progress of eye conditions. But until now most of the treatments they have carried out have been for relatively rare problems, such as choroideremia – which affects 1,200 people in Britain – and retinitis pigmentosa, which affects 16,000.

Now the jab will try to stop agerelated macular degeneration – known as AMD – which is the most common cause of blindness and affects 600,000 people in the UK.

The team is carrying out a trial of ten patients at Oxford Eye Hospital. The small trial is mainly designed to test its safety.

But in time it should give an indication whether the treatment will work, in which case a much larger trial will be launched.

This trial is focusing on dry AMD, which involves a slow deterioration of the cells at the back of the eye. It affects the central part of a patient’s vision with gaps or ‘smudges’, making everyday activities like reading and recognising faces difficult.

The operation involves detaching the retina and injecting a solution containing a virus underneath. The virus contains a modified DNA sequence, which infects cells and corrects the genetic defect that causes AMD.

The first patient, Janet Osborne, 80, from Oxford, had the treatment under local anaesthetic last month. She said the central vision in her left eye has deteriorated and is very hazy, making household tasks extremely difficult.

‘I still enjoy gardening with my husband Nick, who grows a lot of vegetables,’ she told BBC News. ‘If I can keep peeling and cutting the veg, and retain my current level of independence, it would be absolutely wonderful.

‘I wasn’t thinking of me, I was thinking of other people. For me, I hope my sight doesn’t get any worse. That would be fantastic. It means I wouldn’t be such a nuisance to my family.’

Project leader Professor Robert MacLaren, whose trial is funded by gene therapy company Gyro- scope Therapeutics, said: ‘AMD is the number one cause of untreatable blindness in the developed world. A genetic treatment administered early on to preserve the vision in patients who would otherwise lose their sight would be a tremendous breakthrough and certainly something I hope to see in the near future.’

It is hoped that the gene therapy would only need to be performed once, as the effects are believed to be long-lasting.

Professor MacLaren said: ‘We’re harnessing the power of the virus, a naturally occurring organism, to deliver the DNA into the patient’s cells.

‘When the virus opens up inside the retinal cell it releases the DNA of the gene we have cloned, and the cell starts making a protein that we think can modify the disease, correcting the imbalance of the inflammation.

‘We hope that in future it will slow down the progression of macular degeneration.’

Surgeons want to test the treatment on patients with early AMD – and therefore stop the disease before their vision has even started to deteriorate.

‘Stop disease before vision deteriorates’