Diabetes is hot, but few see diabetic blindness

Estimates suggest that 79.4 million Indians will be affected by diabetes by 2030, of which approximately 20% could lose their vision.

Furthermore, a diabetic is 25% more likely to go blind than a non-diabetic.
Given these numbers, the potential for diabetic retinopathy — a disease affecting the blood vessels of retina thereby causing blindness, seems to be very high.

 Ironically, even as pharmaceutical companies jostle to bring out novel molecules for diabetes — valued by Grail Research at about $480 million in India in 2008 and growing at 16-20% per annum — research for new drugs for diabetic retinopathy is nearly negligible.

Major Indian firms such as Glenmark Pharmaceuticals, Piramal Healthcare, Dr Reddy’s Laboratories and Cadila Healthcare have pipelines for diabetes, but the focus towards retinopathy is missing.

US drug major Eli Lilly is one of the only companies conducting clinical trials for a drug targeted for diabetic retinopathy, called ruboxistaurin.

The current available treatment options for the ailment are also limited — laser treatment, avastin injection and surgery.

“Cholesterol lowering drugs like statins are also found to be useful in reducing incidence of diabetic retinopathy,” said Padmaja Kumari, consultant, Retina & Vitreous Centre, LV Prasad Eye Institute, Hyderabad.

However, no oral medication is currently available for treating this ailment, said Barun K Nayak, head, ophthalmology, P D Hinduja Hospital & Medical Research Centre, Mumbai.

“Oral drugs for this ailment are nowhere in the near horizon. Diabetic retinopathy is a huge problem... Less than 20% of retinopathy gets detected early amongst diabetics,” Nayak said.

Also, current treatment options carry a huge cost burden. S Natarajan, chairman and MD, Aditya

Jyot Eye Hospital, Mumbai, told DNA, “Laser ttreatment costs about Rs 3,000 per sitting and avastin can cost around Rs 10,000-15,000 per sitting. Patients may require multiple sittings.”

Moreover, laser treatment — though rare — can lead to decreased night vision and side vision, while avastin has side effects like infection, cardiovascular complications, cataract, etc, say healthcare experts.

Given the high costs of current treatments and the side effects involved, what prevents pharma companies from developing oral drugs for retinopathy?

The companies say they’re looking at prevention, rather than cure.

A spokesperson for a Mumbai-based drugmaker which has a novel diabetes molecule, said the research aim of drugmakers has been to control diabetes, rather than focus on complications like retinopathy.

“We are aiming at controlling diabetes, so that the complications like blindness won’t progress,” the spokesperson said.

The medical director (India) of a leading Europe-based multinational company said that therapeutic focus depends on a company’s strategy and core competence, and that retinopathy is an altogether different area.

“For tackling retinopathy, you have to understand the functioning of the eye. Several companies don’t have expertise in this area,” the executive said.