Tests are looking positive for a new drug to treat a form of childhood blindness.

An international research project has led to a new oral medication which has shown great progress in restoring vision to patients with Leber congenital amaurosis (LCA).

Until now, the inherited retinal disease has remained untreatable, causing impairment ranging from reduced vision to complete blindness.

The study has been published in the journal The Lancet.

“This is the first time that an oral drug has improved the visual function of blind patients with LCA,” says the study's lead author, Dr. Robert Koenekoop, a researcher at Canada’s McGill University.

“It is giving hope to many patients who suffer from this devastating retinal degeneration.”

“The drug changed my life,” says Jörgen, a 44-year-old Swede who was born with LCA, and has long dreamed of a treatment for his blindness.

He showed the most significant improvements of all the participants in the study, who hailed from North America, Europe, China and Brazil.

“My visual acuity and visual field increased significantly,” Jörgen says.

“I can now go by myself into a shopping centre or to the airport and even take the metro, which were unthinkable for me before.

“I hope many people can access the drug in a near future,” he said.

The study involved 14 participants from around the world with LCA ranging in age from 6 to 38 years old.

Their blindness was caused by either mutations in the genes RPE65 or LRAT, leading to a serious defect in the retinoid cycle.

The retinoid cycle produces a molecule called 11-cis retinal which has the special capacity to capture light and initiate vision, making it fundamental for seeing.

Patients with RPE65 or LRAT mutations cannot produce this crucial molecule thus the retinal cells cannot create vision, and slowly die.

“By giving patients with RPE65 or LRAT mutations an oral retinoid intermediate (QLT091001) most patients' vision improved rapidly. We discovered that a certain portion of the retinal cells that were not working because of the lack of 11-cis retinal could be woken up,” explained Dr. Koenekoop.

“Contrary to what was previously thought, children with LCA and defects in RPE65 or LRAT are not born with dead retinal cells; the cells can simply go dormant, and they can remain dormant for years before they eventually die.

“The oral drug we tested awakened these cells and allowed patients to see,” he said.

Ten out of the 14 patients expanded their visual fields; others improved their visual acuity.

The research team performed brain scans of the visual cortex, which showed marked improvements in brain activities in patients who also improved in field size and acuity.

More research will now be conducted to learn about the retinal function in blind people in relation to dosage and methodology.