Viewed as new ray of hope for millions of visually disabled people worldwide, a new drug to treat common forms of blindness is ready to go for clinical trial.  

According to the British media Friday reports, the scientists at the University of Bristol have developed the drug to treat eye diseases affecting the elderly and diabetics, such as age-related muscular degeneration (AMD) and diabetic etinopathy. Successful experiments in mice have shown that the new drug can tackle two of the leading causes of blindness.

The news of the development of the new drug has comes just days after scientists in the United States had claimed that a bionic eye which can restore sight to the blind would be available commercially within two years. The University of Utah study, published in Nature Medicine, provided clues for treating the diseases. According to the study, activating a specific protein in the eyes prevented blood vessel damage which can cause sight loss. The study had implications for macular degeneration and diabetic retinopathy - two common conditions associated with blood vessel problems. These two eye problems are common in older people, and involve both leakage of blood vessels within the eye, and the formation of abnormal new blood vessels.

According to the study, the protein identified as Robo4 plays an important role in the development of stable, working blood vessels. The proteins were activated in mice bred to mimic the effects of age-related macular degeneration (AMD) and diabetic retinopathy. The scientists saw that the blood vessel damage was prevented, or in some cases, reversed.

The researchers described the study as a "major breakthrough", while this does not prove that the same principle works in humans, or that a drug could be developed to harness this without side-effects. The scientists reckoned that it will still take some years before a working drug can be provided for patients.

Professor Randall Olson, director of Utah's John A Moran Eye Center, said, "We are excited about taking this opening and moving the frontier forward with real hope for patients who have but few, often disappointing options."
Dr Hemin Chin, from the US National Eye Institute, said, "Given that vascular eye diseases, such as age-related macular degeneration and diabetic retinopathy, are the number one cause of vision loss in the US, the identification of new signalling pathways that prevent abnormal vessel growth and leakage in the eye represents a major scientific advancement."
In the current study, the team of researchers led by Prof Dave Bates and Dr Steve Harper of the varsity's Microvascular Research Laboratories has identified a novel, naturally occurring form of a compound which inhibits the formation of new blood vessels -- a major cause of the "wet" type of AMD and also diabetic retinopathy. The research has been funded by Britain's leading eye research charity, Fight for Sight.