Diabetic retinopathy eye drop treatment to be developed
Researchers are hoping to develop eye drops for the treatment of diabetic retinopathy.
A team from the University of Nottingham has received a £60,000 grant and if successful, the eye drops could be available to people with diabetes on clinical trials within the next three to five years.
They will be investigating whether work aimed at developing eye drops for the condition age-related macular degeneration (AMD) could also work to prevent sight loss in people with diabetes.
Professor David Bates from the the university’s School of Medicine said: “We are extremely grateful for the grant we have received from the Freemasons and National Eye Research Centre. Without their support, this project would not have been possible and we would not be able to find out whether drugs that are already being developed for other eye diseases could be also be used in diabetic retinopathy.
“Diabetes is the leading cause of preventable sight loss in the working population in the UK. The impact of this research means that in the future diabetic patients could be offered a better, more effective way of preventing them from losing their sight.
“The current treatment for diabetic retinopathy is very unpleasant for the patient but also costly and time-consuming because the injection can only be performed at eye clinics by specialist doctors and nurses.”
In the human body, a protein called VEGF (vascular endothelial growth factor) is responsible for the normal formation and growth of blood vessels. However, in people with diabetes a type of VEGF is produced which causes the faulty blood vessels to grow and leak fluid into the eye. Current treatments target all forms of VEGF which prevent the growth of the faulty blood vessels but also stops the re-growth of normal blood vessels to help the eye recover from the effects of the high blood sugar levels.
Studies have shown that in models of AMD, drugs can be used to target the protein SRPK1 which can switch off the detrimental form of VEGF and enable the good form of VEGF to promote normal blood vessel growth and protect the endothelial cells which line the interior surface of the blood vessels.
The current drug, which is used to switch off VEGF completely, is a large molecule, meaning it can only be administered by injection. However, the drugs which target SRPK1 are much smaller meaning that they could be given in the form of eye drops.
professor Bates said: “Eye drops that patients could administer themselves would reduce both their discomfort and the financial burden which the current treatment places on the NHS.”
Around 1.2 million people are believed to suffer from diabetic retinopathy in the UK, with around 750,000 of those currently experiencing some form of visual impairment.
The Royal National Institute for the Blind (RNIB) estimates that the total economic cost of sight loss including healthcare, social care and loss of employment, could be as high as £28bn per year. Globally, the condition affects in the region of 93 million people.
Diabetic retinopathy is a complication of diabetes caused by high blood sugar levels. Over time it can weaken and damage the small blood vessels within the retina which can cause haemorrhages, leaky blood vessels and swelling on the retina. This starves the retina of oxygen, causing abnormal blood vessels to grow. If left untreated over time it can affect vision and lead to blindness.
In more serious cases, the leaking blood vessels behind the eye can lead to the condition diabetic macular oedema in which fluid builds up in the macula, the part of the eye which provides us with our central vision. The condition of patients with diabetic macular oedema can decline very quickly and can lead to rapid visual impairment and blindness.