A gene therapy developed by University of Florida scientists restored useful vision to most patients with rare condition Leber congenital amaurosis type I (LCA1) in a small trial.

Patients who received the highest dose of the gene therapy saw up to a 10,000-fold improvement in their light sensitivity, were able to read more lines on an eye chart, and improved in their ability to navigate a standardised maze.

The trial also tested the safety profile of the treatment. Side effects were largely limited to minor surgical complications. The gene therapy itself caused mild inflammation that was treated with steroids.

“This is the first time that anyone with LCA1 has ever been treated, and we showed a very clean safety profile, and we also showed efficacy. These results pave the way for advancing the therapy in a Phase III clinical trial and eventually commercialising it,” said Shannon Boye, Chief of the Division of Cellular and Molecular Therapy at UF, co-author of the study and co-founder of Atsena Therapeutics.

In collaboration with her husband Sanford Boye, Shannon Boye’s lab developed the virus-based transport system that is essential for delivering functioning copies of the GUCY2D gene into the correct cells in the eyes.

A breakthrough in LCA1

The Boyes founded Atsena Therapeutics in 2019 to bring the LCA1 treatment and other gene therapies to market.

“Atsena is pleased to advance the foundational work that Shannon and Sanford Boye developed in their laboratory many years ago and thrilled that the 12-month data from our ongoing clinical trial have been published in a prestigious medical journal,” said Kenji Fujita, Chief Medical Officer of Atsena Therapeutics and co-author of the study. “We look forward to sharing further results from this programme as we continue progressing what has the potential to be a breakthrough in treating blindness in children and adults with LCA1.”

The study enrolled 15 subjects who received the treatment in one eye, which involved a surgical injection in the retina.

Researchers followed the patients for a year to test their vision in the treated eye compared to the untreated eye. Subjects who received higher doses saw greater improvements in their vision. So far, they have seen visual improvements last at least five years.

Diana Spencer, Senior Digital Content Editor, DDW