Retinitis Pigmentosa

Retinitis Pigmentosa is a rare condition which progressively causes vision loss. Genetic lesions which first affect the rod photoreceptors first cause vision loss at night. Next, cone photoreceptors are impacted which impacts vision during the day.

One thing that makes this condition difficult to treat is that there are many different genetic mutations which can cause it. Currently, there are a few gene therapies available for some of these unique mutations which impact the photoreceptors. Unfortunately, there has yet been a therapy which combats all of the mutations.

A universal gene therapy for retinitis pigmentosa would be life-changing, and that is what a recent study aimed to do.

The Study

The lead author on this study was Yunlu Xue from Harvard. The study aimed to investigate a gene therapy which would be widely effective for all retinitis pigmentosa patients.

Xue and their colleagues investigated 20 different therapies in mice models. These therapies were hand-picked.

They found that the gene Txnip was was effective in three different models. The team used a viral vector to deliver the gene to all of the mice. In particular, they found that C247S, a version of Txnip was especially effective. This form of the gene allowed the cone photoreceptors to begin to use other forms of energy. The therapy also created improvements in mitochondria health.

Additionally, the gene therapies used in this study-

• Reduced oxidative stress
• Reduced inflammation
• Improved cell protection

The next step is to conduct other safety studies and then to move on to a clinical trial with human patients.

Looking Forward

Researchers are excited about the prospects of this therapy not only for treating a wide array of retinitis pigmentosa patients but for improving other conditions which caused vision loss such as macular degeneration.

Ultimately, Txnip, and Txnip in combination with additional gene therapies, may improve eye health and vision for those suffering from vision loss.

You can read more about this study and investigative gene therapy here.