An experimental gene therapy developed at the Telethon Institute of Genetics and Medicine (TIGEM) in Pozzuoli has shown encouraging clinical results in patients with Usher syndrome type 1B, a rare genetic disorder that causes congenital deafness and progressive vision loss. The first data, presented one year after the start of the clinical trial, show a significant improvement in visual capacity without serious adverse events.
The therapy was administered for the first time in the world at the Eye Clinic of the University of Campania “Luigi Vanvitelli”, the lead center of the trial. The first treated patient, a 38-year-old man, experienced substantial vision improvement after twelve months, both at near and far distances and in low-light conditions.
“Now I can recognize faces, see the warehouse aisles at work, and read subtitles on TV. It’s not just about seeing better — it’s about starting to live again,” the patient shared.
Usher syndrome type 1B is caused by mutations in the MYO7A gene, which is too large to be delivered using standard viral vectors commonly used in gene therapy. To overcome this technical limitation, TIGEM researchers developed an innovative platform based on a dual-vector system: two modified viruses each carry half of the gene, allowing the cell to reassemble the information and produce a complete and functional version of the missing protein.
“Gene therapy is already a therapeutic option for several rare diseases, but technological limits still exist. Our platform makes it possible to extend this option to diseases caused by large genes,” explained Alberto Auricchio, Director of TIGEM and Scientific Director of AAVantgarde Bio, a biotech company sponsoring the clinical study, established thanks to initial funding from the Sofinnova-Telethon fund.
The treatment is performed under general anesthesia, with the vectors injected beneath the retina. “The procedure is not particularly invasive, and the improvement in visual acuity can be seen within a few weeks,” explained Professor Francesca Simonelli, Director of the Advanced Ocular Therapies Center at Vanvitelli University. “In the first patient treated, improvement was evident after two weeks and continued progressively.”
In addition to the first case, seven other patients were treated between October 2024 and April 2025 as part of the ongoing international phase I/II LUCE-1 study. Two different dose levels (low and intermediate) have been tested so far, and a higher dose will be tested in the next group of seven patients. Data collected to date confirm the safety and tolerability of the therapy: the few observed cases of ocular inflammation were mild and manageable with corticosteroids.
These preliminary results mark an important first step in assessing the clinical effectiveness of this new technology. “The trial is still ongoing, but the signals we’ve seen so far open promising avenues for other inherited retinal diseases currently lacking treatment options,” Simonelli added.
Fondazione Telethon has supported the work of these researchers for over ten years, with the goal of making effective treatments available for rare genetic diseases previously considered untreatable with standard gene therapy.
