High hopes for 4-year-old’s vision after gene therapy

Health Care
Luxturna gene therapy
Luxturna gene therapy
Luxturna gene therapy
“He’s never seen the stars," says Krista Soto, of her son, Caspian, 4. Caspian was born with a rare genetic mutation that severely limits his sight. (OHSU/Kristyna Wentz-Graff)

Throughout his first four years, young Caspian Soto has navigated life differently than most.

He wears a headlamp to brighten the world before him and uses a cane to feel the ground’s surface – and sometimes, for fun, also rides it like a witch on a broom. Without these items, he used to become frustrated as he routinely bumped into objects that were in clear view for others, but hidden to him.

“The headlamp gave him a feeling of control,” explained his mom, Krista Soto, of Portland, Oregon. “It’s been his beacon.”

The lamp and cane have become Caspian’s constant companions, serving as his unique and practical pair of security blankets. Though his parents have assured him he’s welcome to keep both items, he doesn’t actually need them anymore.

One tiny mutation

Caspian was born with a rare mutation in his RPE65 gene, which produces proteins needed for a fully functioning retina -- tissue in the back of the eye that detects light and color. The mutation caused a condition called Leber’s congenital amaurosis in Caspian that turned his vision dark and blurry, making low-light areas a challenge. Until recently, his parents expected the Leber’s would worsen and eventually cause Caspian to go completely blind.

Luxturna gene therapy
Dr. Paul Yang takes a look in Caspian's eyes as he sits on his mother's lap, at the OHSU Casey Eye Institute in July. Caspian is among first in Oregon to have a new gene therapy treatment to treat his vision impairment. (OHSU/Kristyna Wentz-Graff)

The Portland 4-year-old recently became the second patient in Oregon to undergo a new gene therapy treatment at the OHSU Casey Eye Institute. Called Luxturna, it involves injecting a modified virus into a patient’s eyes to correct the RPE65 mutation. The treatment was developed by Spark Therapeutics of Philadelphia and became the first FDA-approved gene therapy for an inherited disease in December. OHSU is one of nine U.S. institutions that currently offer the therapy.

“Gene therapy can give some patients who face the possibility of blindness the gift of restored eyesight,” said David Wilson, M.D., director of the OHSU Casey Eye Institute. “OHSU is proud to offer this treatment and participate in clinical trials for nine other ophthalmologic gene therapies to help give more people a lifetime of vision.”

The OHSU team that cares for patients who undergo this gene therapy includes:

Luxturna gene therapy
Caspian was born with a rare genetic mutation that turned his vision dark and blurry, making low-light areas a challenge. (OHSU/Kristyna Wentz-Graff)

Early worries

As a newborn, Caspian stared at lights and out of windows a lot.

“At first we thought it was cute, but then we realized just how much he was staring,” said his mom, Krista. “And then his eyes started doing this weird rolling thing, and it really freaked us out.”

An MRI ruled out brain tumors and lesions, but a doctor told his parents they’d have to wait and see how his vision would develop. By the time Caspian was two and came to the OHSU Elks Children’s Eye Clinic, he was frequently bumping into tables, walls and other everyday obstacles. A year later, a genetic test revealed he had the RPE65 gene mutation.

“I was relieved because I knew RPE65 was one that there were clinical trials for at the time, and gene therapy to treat it was on the horizon,” Krista said.

‘The world … will open up’

Krista and her husband, Zack Soto, had heard the FDA might rule on Luxturna in January 2018, but then the treatment was surprisingly approved a month earlier. Krista’s birthday is in December, making the announcement “a massive birthday present,” she said.

They knew they wanted to pursue the treatment for their son, but they weren’t sure how they’d cover the $850,000 price tag announced by Spark Therapeutics. Fortunately, their insurance agreed to pay for the procedure.

Caspian had his right eye treated on Sept. 17 and his second eye was treated a week later. Because it takes a while for the treatment’s modified virus to make the proteins needed for good vision, patients typically start seeing improved eyesight about two to four weeks after receiving treatment.

Luxturna gene therapy
Surgeons Andreas Lauer, M.D., (left) and Steven Bailey, M.D., (at scope) treat Caspian's right eye in September. (OHSU/Kristyna Wentz-Graff)

Krista Soto has high hopes for her son’s future.

“He’s never seen the stars. I can’t even take him to the Smithsonian -- and I love the Smithsonian -- because it’s too dark,” Krista Soto said. “To give him the opportunity to experience those things is indescribable. I can’t even begin to fathom the world that will open up.”

Just two weeks after the first procedure, Caspian’s parents began to notice improvements in their son’s vision. For example, they recently visited a local museum and he pointed out a blinking plane as it flew through a night sky.

In the future, OHSU may be able to provide similar hope to other patients with inherited retinal disorders. OHSU is a treatment center for nine different gene therapy trials for other blindness-causing genetic mutations. If the trials are successful, the developers of each treatment may submit them for federal approval so more patients can benefit from a lifetime of eyesight.

To see more photos from Caspian's story, click here.


Franny White
Senior Media Relations Specialist
OHSU
503-494-8231