A leading ophthalmologist has called for a change in clinical practice after an inexpensive cholesterol medication that targets abnormal blood fats in diabetes was found to slow progression of a sight-threatening disease.
Fenofibrate, a lipid-lowering medication that targets abnormal blood fats in diabetes, has been shown to reduce the progression of diabetic retinopathy and reduce the need for laser treatment in two major international trials involving 14,000 people.
Professor Paul Mitchell, Director of the Centre for Vision Research at the Westmead Millennium Institute, said the evidence was now strong enough to warrant a change in clinical practice.
“The greatest benefit was for people with early diabetic retinopathy and there is reason to think that those without retinopathy might also benefit,” he added.
Diabetic retinopathy affects some 300,000 Australians. It occurs when retinal blood vessels swell, leaking into the surrounding tissue, causing oedema and forming abnormal new blood vessels which are prone to bleeding. If left untreated, both these conditions often lead to serious vision loss and even blindness.
The current treatment protocol is laser which seals leaking blood vessels, drying out areas of swelling and helping to prevent vision loss.
The FIELD study, which involved 10,000 people, showed fenofibrate resulted in more than a 30 per cent reduction in the use of laser treatment for two forms of diabetic retinopathy – macular oedema, which damages reading and driving vision, and proliferative retinopathy, which can lead to major haemorrhage and severe vision loss. The benefits were evident within 12 months of treatment.
The more recent ACCORD study, which involved an additional 4,000 people, showed a 40 per cent reduction in retinopathy progression with fenofibrate.
Speaking at the Asia Pacific Academy of Ophthalmology (APAO) Congress, Professor Mitchell said it was unlikely that studies of such size and significance would be repeated.
He said uncertainty about how exactly the medication worked on retinopathy had possibly slowed its uptake.
“Many people with diabetes are already on other lipid-lowering medications. Statins, for example, are a different class of medication and have been shown to reduce cardiovascular risk. However, statins do not appear to influence diabetic retinopathy, “However, fenofibrate is more effective in treating the particular blood fat issues associated with diabetes – high triglycerides and low levels of high density lipoproteins (HDL),” said Professor Mitchell.
“It was also possible that fenofibrate impacted on diabetic retinopathy via a mechanism unrelated to its effect on blood lipids,” he added.
According to Professor Mitchell, fenofibrate is an established drug which has been around for about 30 years, is inexpensive and safe.
“By halting the progression of retinopathy, it could help preserve vision and reduce the need for costly therapies for advanced disease.
“This is a new reason to use an old drug. One tablet, once a day, can prevent sight threatening damage to the retina in people with type 2 diabetes,” concluded Professor Mitchell.
Fenofibrate is officially indicated for its role in treating lipid abnormalities in diabetes, but is not yet approved for its role in reducing retinopathy.