European consortium launches first human trial of gene-silencing eye drops for rare eye diseases

Two studies opening at University of Cologne (Germany) will test whether a new class of eye drops silencing Insulin-Receptor Substrate 1 (IRS1) can slow the vessel growth that damages the cornea in patients with aniridia and those facing high-risk corneal transplants.

For people born with aniridia, a rare genetic condition, the surface of the eye slowly breaks down over time. Blood vessels that should not be there creep across the cornea, clouding vision in a process that cannot currently be stopped. For patients who have had corneal transplants, the same vessel growth is a serious threat — it is one of the main reasons transplanted tissue is rejected. Now, a European research project is testing whether a specific kind of eye drops could help change that.

“We invite patients with Aniridia and progressive corneal neovascularisation to get informed about this pilot clinical trial. Together with Laboratoires KÔL in France producing the eye drops we are glad to finally be able to have a topical inhibitor of angiogenesis as potentially new treatment option available.”

– Prof. Dr. Claus Cursiefen, Principal Investigator and Chairman, Dept. of Ophthalmology, University of Cologne.

“Currently there is no adequate targeted treatment option for corneal neovascularization in clinical routine. In the case of aniridia-associated keratopathy, our options are further limited due to the complex and rare nature of this pathology.”

– Dr. Mert Mestanoglu, Study Physician, Department of Ophthalmology, University of Cologne

Researchers from the EU-funded project Restore Vision have begun recruiting patients in Cologne, Germany, for the first human trial of eye drops designed to silence the gene signal responsible for the abnormal vessel growth that drives both orphan diseases. The eye drops are antisense oligonucleotides known as OLISENS, and work by blocking the expression of a specific protein called IRS-1 that triggers blood and lymphatic vessels to invade the cornea, the clear front surface of the eye. Once those vessels take hold, they cloud vision and, in transplant patients, dramatically increase the risk of rejection.

Patient recruitment has opened at Department of Ophthalmology at University of Cologne, Germany, for two studies in aniridia and in high-risk corneal transplant patients marking the first time this treatment will be tested in patients with these rare diseases (EudraCT / EU CT No.: 2025-522609-39-00 and 2025-522099-10-00). The eye drops had already been granted with an orphan drug designation, a special status for medicine against a rare condition. The trials are an early-phase safety and efficacy study. They sit within a broader European programme called Restore Vision developing treatments for seven rare eye diseases affecting an estimated 500,000 people across Europe. Aniridia alone affects around 1 in 100,000 people.

“For us, this project is very important because it represents a real opportunity to develop safe and effective treatments for patients with rare eye diseases. That is why Aniridia Europe is engaged in the project and highlights the vital importance of clinical trials. We strongly believe that bringing together researchers, clinicians, and patient representatives is the key to accelerating scientific breakthroughs and ensuring that new discoveries lead to treatments that truly make a difference for patients and their families.”

– Barbara Poli, President Aniridia Europe – member organisation of the Restore Vision project.

“This is a very significant milestone in our quest to develop novel therapies for patients suffering from rare eye disease. This will contribute to make novel drugs more accessible for patients suffering from rare eye disease.”

– Prof. Thomas Ritter, Restore Vision Project Coordinator, Galway

Who can take part?

The OLISENS-ANIRIDIA and OLISENS-PRECON studies are now recruiting at Dept. of Ophthalmology, University of Cologne, Germany. Eligible participants include patients diagnosed with aniridia-associated keratopathy, or patients scheduled for or who have previously undergone a high-risk corneal transplantation. The Dept. of Ophthalmology at University of Cologne performs the highest number of corneal transplants in Europe.

Full eligibility criteria, study details, and contact information for the clinical team are available at UKK’s website.

Further trials in preparation across Europe

The Cologne studies are the first of several first-in-human clinical trials planned under Restore Vision. Additional sites at INSERM in France and Ospedale San Raffaele in Italy are currently in preparation, with trials targeting further rare corneal and ocular surface diseases within the consortium’s scope.

Updates on recruitment progress and other project milestones will be published on the Restore Vision website and communication channels.

Clinical trials at a glance

About Restore Vision

Restore Vision is a Horizon Europe-funded research project coordinated by the University of Galway, Ireland. The consortium brings together 10 partnering leading research institutions, SMEs, and patient organisations from across Europe to develop innovative therapies for rare corneal and ocular surface diseases. By combining expertise in research, clinical development, industry, and patient advocacy, the consortium aims to accelerate the development of treatments that can improve the lives of people living with rare eye diseases.

Funding acknowledgement

This project has received funding from the European Union’s Horizon Europe research and innovation programme under grant agreement No. 101080611. The contents of this press release are the sole responsibility of the Restore Vision consortium and do not necessarily reflect the opinion of the European Union.

Media contact

Name: Vera van de Donk – Communication and Dissemination Lead (Catalyze)

Email: restorevision@catalyze-group.com

Web: www.restorevision-project.eu