Researchers have developed a new gene therapy which could help improve the vision of patients with inherited retinal diseases.
According to the research which was presented at the AAO 2017, the 121st Annual Meeting of the American Academy of Ophthalmology, the patients with the condition called Lebel congenital amaurosis (LCA), which begins during infancy and develops as complete blindness could be cured with gene therapy.
Ophthalmologist Stephen R. Russell of the University of Iowa treated 29 LCA patients with the new gene therapy and found that 27 patients had undergone improvement in their vision which could allow them to navigate through a maze, even in the low and medium light. The patients also experienced improvements in their light sensitivity and peripheral vision.
The LCA has been found in 1 out of 80,000 individuals and is regarded as a very rare vision impairment. It is believed to be caused by one or more genes out of the 19 different genes which are found in a sequence.
The treatment, called voretigene neparvovec or Luxturna Spark Therapeutics, involves an injection of a genetically modified harmless virus into the patient's retina. Billions of genetically modified viruses are injected into both eyes of the patient.
The therapy has been tested so far in more than 200 LCA patients since 2007 and it was found that most patients have had their visions for more than two years.
However, the treatment does not completely restore the patient's normal vision. It allows the patient to see light and shapes and could help them to travel without another person's support, cane or a guide dog.
The gene therapy, which is first of its kind, is being reviewed by the U.S. Food and Drug Administration for approval. The researchers hope that the approval could help in further studies in the field of inherited retinal diseases which doesn't have any proper treatments currently. There are 225 gene mutations which were found to cause blindness.