Abu Dhabi: Two Emirati sisters from Abu Dhabi have become the first to receive gene therapy in the UAE, it was announced in the capital today.
The therapy was conducted with the aim of saving the vision of Alia, 13, and Hessa, 11, who suffered from retinal damage due to a defective gene.
The vision-saving surgery was performed at Cleveland Clinic Abu Dhabi in January (2020), and doctors said at a press conference that they are hopeful it will slowly improve the vision of both patients.
"The prospect of slowly losing one's vision from an untreatable condition is traumatic for both children and their parents. This genetic therapy means we can now replace the faulty gene in the eye, saving and even improving the vision of an individual who would otherwise have eventual irreversible blindness," said Dr Arif Khan, paediatric ophthalmologist and ocular geneticist at the hospital.
Only centre in region with procedure
Cleveland Clinic Abu Dhabi is only one of 10 centres worldwide, and the only one in the region, that is qualified to offer this procedure - the first gene therapy that was approved by the Food and Drug Administration in the United States, doctors said. But its availability opens the doors for more gene therapies to be offered to treat conditions as varied as diabetes and spinal muscular atrophy, they added.
“We’ve travelled abroad multiple times to find some treatment for our daughters, and this procedure has been a godsend. It has only been a month since the therapy however, and we are hoping for much more improvement to their vision over time,” Fatima, the girls’ mother, told Gulf News.
Alia and Hessa were born with RPE65-related retinal dystrophy, a genetic dystrophy in which the RPE65 protein is lacking because a child inherits two copies of the defective RPE65 from both parents. It is a recessive disease and therefore rare, and known to affect one in 200,000 people worldwide. But the condition is also more common in the region because of the limited genetic pool and cultural preferences for consanguineous marriages.
Patients with the condition face gradual damage to their retinas, the photosensitive layer at the back of the eye, and could eventually end up with irreversible blindness.
The gene therapy to treat the condition uses a vector - a bioengineered non-pathogenic virus – to deliver normal copies of the RPE65 gene to the eye.
“The procedure takes only about an hour, but it is very delicate. The retina can be considered an offshoot of the brain because its cells are very thin, like brain tissue. We use advanced microscopes to create openings in the white of the eye, then use a specialized canula to reach under the retina and inject the vector into the specific area, which can be as small as one-tenth of a millimeter,” explained Dr Emad Abboud, chief of the department of the posterior segment at the hospital’s Eye Institute.
Post-surgical recovery takes only about a week, but outcomes take a while to become obvious.
As Dr Khan explained, the main benefits for patients receiving the therapy is an improvement of vision in low-light conditions, and an improvement of the visual field.
“Vision is a complex sense, involving photosensitivity, visual field, visual acuity, colour sensitivity, motion sensitivity, and the ability to navigate. But [at the least], this therapy prevents the progressive deterioration of the retina,” he explained.
What the family said
“My handwriting has definitely gotten better,” Alia told Gulf News when asked about how the therapy has helped.
“I can’t tell what else will get better but I already feel that this has been life-changing,” she added.
According to Fatima, she noticed her daughters had visual impairment when they were as young as two months old.
“The doctor pointed out to me that they were not focusing or making eye contact. So we were aware of the condition. It definitely made life very challenging, especially as their development was delayed,” the mother explained.
Alia and Hessa both crawled and walked late, and have needed assistance getting around. While they kept pace with their peers at school, it took Hercualean efforts from both girls, their parents, shadow teachers and at-home tutors, and required the use of Braille and visual aid resources.
Fatima and her husband, Mubarak, kept looking for treatments for both girls, travelling to Germany, India and Spain.
“In 2016, we visited the Cleveland Clinic Abu Dhabi, and it was then that we heard of this revolutionary treatment. It was still not approved by the FDA, but we kept dreaming,” she said.
“It has been a month since the surgery and the doctors said they are more photosensitive now and that this is a good sign. Of course, as a mother, I would love for them to eventually have complete vision,” Fatima added.
What is the therapy?
The UAE Ministry of Health and Prevention (MoHAP) approved the gene therapy for RPE65-related retinal dystrophy, Luxturna, in June 2019.
In a statement released at the time, the MoHAP said its registration of Luxturna was only the third global registration of the ‘drug’ at the health authority level, and was aimed at paving the way for future gene-based therapies for complex conditions.
The United States’ Food and Drug Administration only approved Luxturna, developed by gene therapy developer, Spark Therapeutics, and the Children’s Hospital of Philadelphia, in late 2017.
The gene therapy to treat the condition uses a vector - a bioengineered non-pathogenic virus – to deliver normal copies of the RPE65 gene to the eye with the defective gene.
While the Cleveland Clinic Abu Dhabi did not provide the cost of treatment, international media reports put it at $425,000 (Dh1.56 million) per eye.
Benefits of gene therapy
Dr Khan said at the press conference that us familiar with a few more families with the RPE65-related retinal disorder.
“Over time, gene therapy could be used to treat many conditions. The eye is uniquely suited for these therapies because it is a self-contained organ. But at least five other genetic therapies are in development, some at the human trial level,” he explained.
“Consider gene delivery to be like providing a protein factory to the body. So for instance, some diabetic patients require regular insulin injections. If a gene could be engineered to make insulin, and it could be delivered to the patient, he wouldn’t need these regular injections,” Dr Khan added.