A new gene therapy procedure shows great promise for the treatment of the rare eye disease Leber congenital amaurosis LCA). Researchers believe this new treatment could help thousands of child patients stave off LCA's severe symptoms like vision loss and blindness.
29 LCA patients took part in this American study. All study participants were given the gene therapy procedure known as Luxturna (officially called Voretigene neparvovec). The biotech company Spark Therapeutics developed Luxturna with the help of the Children's Hospital of Philadelphia.
To test the efficacy of Luxturna, researchers made patients walk through a maze in dim light. They found that 27 of the 29 patients were able to successfully navigate the maze after undergoing Luxturna treatment. Study authors also noted that most patients were better able to distinguish different shades of light and had a stronger peripheral vision after one Luxturna therapy.
All of these findings were presented at the 2017 American Academy of Ophthalmology (AAO) meeting. This year's AAO meeting was held in New Orleans's Ernest N. Morial Convention Center from November 11th to the 14th.
Just one dose of Luxturna can replace the dysfunctional RPE65 gene with a healthy gene in LCA patients' eyes. People with LCA have dysfunctions with the RPE65 gene, which is located in the retina.
Another longer-term study found that one Luxturna treatment helped improve the vision of children with LCA over three years. Spark Therapeutics is still observing the long-term effects of this therapy.
Unfortunately, it will cost LCA patients $425,000 per eye to receive a Luxturna treatment in one eye. Believe it or not, this is less than the expected $1 million per eye some analysts predicted.
Spark Therapeutics has said it's working with insurance companies to help bring this cost down even further. As of today, Spark is in talks to partner with insurance providers such as Express Scripts and Harvard Pilgrim.
The Food and Drugs Administration (FDA) approved Luxturna for use in the treatment of LCA in December of 2017. The only major side-effects noted with Luxturna include increased intraocular pressure, eye redness, and eye swelling.
LCA is classified as a genetic disorder and most symptoms appear in childhood. A few key indicators of LCA include involuntary eye twitching, delayed pupil responses, or extreme vision loss.
Doctors believe this disorder adversely affects the retina's photoreceptor cells. There are currently 18 different genetic codes associated with LCA.
LCA was named after the German ophthalmologist Theodor Karl Gustav von Leber. Dr. Leber, who lived from 1840 to 1917, discovered LCA in 1869.
Current estimates suggest that about 6,000 patients around the world have LCA. Approximately 2,000 of those patients are in America.