Many of us know someone who has slowly lost their sight to a disease that runs in the family.
For a long time, the honest answer was that nothing could bring the vision back. Researchers have now shown there may be another way in.
A small trial enrolled 10 adults who were legally blind from an inherited eye disease.
Seven showed clear gains in how much light they could sense after a single gene therapy injection, according to results published this month in the New England Journal of Medicine.
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Four of the eight who went on to behavioral tests could reach for and point to objects placed in front of them while wearing a specially designed set of goggles. None of them could do that before.
The condition is called retinitis pigmentosa. It is a genetic disease that slowly destroys the light-sensing cells at the back of the eye, often starting with night blindness in the twenties or thirties.
More than 100 different genes can trigger it, and there is no cure.
Gene and goggles work together
The therapy, called GS030, has two parts. First, a single injection delivers a gene into the surviving nerve cells at the back of the retina.
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That gene makes the cells produce a light-sensing protein called ChrimsonR, which normally lives in algae.
ChrimsonR only reacts to a narrow band of amber light the eye does not meet in daily life. That is where the second part comes in.
A small camera on a pair of goggles films the world around the wearer.
A projector then feeds the images back into the eye as pulses of amber light at the right wavelength to switch the modified cells on.
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What the trial could and could not show
The study ran at hospitals in Paris, Pittsburgh and London and was led by José-Alain Sahel, an ophthalmologist at the University of Pittsburgh School of Medicine.
The 10 participants had an average age of about 55 and had all lost most of their sight.
Across the group, the biggest gains were in basic light detection. Four of the eight who completed object tests also improved at spotting, locating and reaching for items on a table.
The treatment did not restore detailed or color vision. People could not read with it, and the trial was small, open label and had no comparison group.
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Larger studies are needed to show how well it works and how long the effect lasts.
Side effects were mostly mild or moderate, such as temporary eye inflammation. One participant had a severe but brief blockage in a retinal artery that resolved within minutes.
Patients today
GS030 is still experimental and is not available outside clinical trials.
Anyone with retinitis pigmentosa or another progressive eye disease should talk to an ophthalmologist about current standard care and any trials they may qualify for.
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This article is made and published by Ida-Marie Palm Varbæk, who may have used AI in the preparation.