New drug a breakthrough in the treatment of AMD

Oct 5 2006

Age-related macular degeneration (AMD), is a common cause of vision loss and often affects older people.

The disease is caused by an inappropriate growth of blood vessels around the retina and when these immature blood vessels leak and ooze, they damage cells in the retina and affect vision.

Current treatments using lasers and photodynamic therapy had been able to slow down the progression of the disease but patients ultimately still lose their vision.

Now a new drug has been found to slow down and even improve sight in some patients.

Lucentis (ranibizumab) used to treat wet age-related macular degeneration (wet AMD), which affects thousands of people in the UK alone, slowed vision loss in around nine out of 10 patients, and improved vision for about a third.

The drug has already been approved for use in the U.S. but has yet to be granted a European licence and still has to be appraised by the National Institute for Health and Clinical Excellence (NICE).

Ranibizumab is one of a class of drugs known as anti-angiogenics and prevents the formation of abnormal, new blood vessels in the eye, and dries up vessels which have already begun to leak.

The 716 patients who took part in the study were given eye chart tests before and after receiving the drug, or a placebo and it was found after two years patients taking 0.3mg of Lucentis were able to read on average 5.4 more letters on the sight chart while those taking the placebo drug were able to read 14.9 fewer letters.

A quarter (26%) of those receiving 0.3mg of the drug and 33% of those receiving 0.5mg also experienced improvements in their sight, compared with 4% on the placebo.

This meant they could read an additional three lines or 15 or more letters on an eye chart after a course of treatments.

The Royal National Institute for the Blind (RNIB), says the results are very exciting as thousands of people a year in the UK get wet AMD and it rapidly leads to sight loss; they say the drug is particularly exciting because it can treat all types of AMD.

Around 20,000 people in the UK are estimated to suffer from wet AMD, while up to 500,000 suffer from both the wet and dry forms of the condition.

AMD affects the central part of the retina at the back of the eye which is responsible for the central vision necessary for everyday activities such as reading, driving, telling the time or identifying faces.

Wet AMD, is very aggressive and responsible for 90% of cases of blindness caused by the condition.

Apart from aging, smoking and genetic factors are thought to increase the risk of developing the condition.

Experts say the treatment works best in patients with newly diagnosed macular degeneration and the results represent the biggest breakthrough in the history of the treatment of macular degeneration.

The research is published in the New England Journal of Medicine.