Paris, France, Thursday, October 8, 2026, 8:30 am CET – GenSight Biologics (Euronext: SIGHT, ISIN: FR0013183985, PEA-PME eligible), a biopharma company focused on developing and commercializing innovative gene therapies for retinal neurodegenerative diseases and central nervous system disorders, and the 15-20 National Hospital (l’Hôpital national des 15-20) in Paris today announced the publication of the results of the GS030 PIONEER trial in the prestigious medical journal The New England Journal of Medicine (NEJM).

Available in the October 8, 2026 issue of the NEJM, the article reports the trial’s primary safety findings and exploratory visual function assessments evaluating GS030, GenSight Biologics’ candidate optogenetics treatment for late-stage retinitis pigmentosa (RP). GS030 uses an intravitreal injection of an AAV-based gene therapy that encodes light-sensitive proteins in the intact retinal ganglion cells of one eye, coupled with light-stimulating goggles to activate the light-sensitive proteins.[1]

Published a few days after the awarding of the 2026 Nobel Prize for Physiology or Medicine to Karl Deisseroth, Peter Hegemann and Georg Nagel for their foundational discoveries concerning light-gated ion channels and optogenetics, the NEJM article illustrates the therapeutic potential of the scientific approach recognized by the prize.

In the field of vision, the publication builds on more than two decades of research into vision restoration through optogenetics, to which Professors José-Alain Sahel and Botond Roska, co-founders of GenSight Biologics, have made major contributions, ranging from fundamental scientific breakthroughs to clinical applications. In recent years, their work in vision and neuroscience has been recognized with several of the world’s most prestigious awards. Teams from the Institut de la Vision and GenSight Biologics have played a key role in advancing the program from the laboratory to the clinic.

Teams from the 15-20 National Hospital, notably within the REFERET rare disease reference center coordinated by Prof. Isabelle Audo, took part in the clinical evaluation of the optogenetic approach alongside leading international centers, including the UPMC Vision Institute in Pittsburgh, Moorfields Eye Hospital in London and Streetlab (www.streetlab-vision.com). This involvement underscores the hospital’s ability to contribute to world firsts in innovative treatments for rare retinal diseases.

“The results mark an important step in the development of optogenetics as an approach to restore vision,” said Prof. José-Alain Sahel, founder and former director of the Institut de la Vision and the FOReSIGHT University Hospital Institute, Exceptional Class Professor Emeritus of Ophthalmology at Sorbonne University, Distinguished Professor in the Department of Ophthalmology at the University of Pittsburgh, Director of the UPMC Vision Institute, and Eye & Ear Foundation Chair of Ophthalmology. “They show that measurable visual responses can be achieved in patients with advanced retinitis pigmentosa, using an approach that bypasses the loss of photoreceptors. These results remain exploratory and will need to be confirmed and further investigated, but they open up a particularly promising avenue for patients who currently have very limited treatment options.”

Encouraging exploratory findings in a study primarily focused on safety

Most ocular adverse events were mild or moderate, with the single event classified as severe resolving within minutes after instillation of Iopidine. There was no systemic adverse event determined to be related to the study drug or to the intravitreal injection.

The study was not designed to establish the efficacy of GS030, but the authors highlight several results that merit further research into the efficacy of GS030.

  • In six of the ten participants, exploratory assessments showed a clinically meaningful improvement in light sensitivity, as assessed with full field stimulus threshold (FST) testing.
  • Four of the 8 participants who completed visual behavioral testing showed positive changes in the ability to perform certain tasks while using the light-stimulating goggles: detecting, localizing or touching objects, or determining the orientation of bars.
  • Exploratory high-density EEG recordings in a subset of participants showed changes consistent with the transmission of optogenetically evoked visual signals to the visual cortex, supporting the interpretation that the observed behavioral responses reflected changes in visual processing rather than being an artifact.

“For patients with advanced retinitis pigmentosa, who still have very limited treatment options, an approach that could restore some form of visual perception represents an especially important prospect,” said Prof. Isabelle Audo, coordinator of the REFERET reference center at the 15-20 National Hospital, team leader in the Department of Genetics and Deputy Director of the Institut de la Vision. “This study also demonstrates the value of patient-centered clinical research conducted through close collaboration among research teams and innovation partners, brought together within the FOReSIGHT University Hospital Institute.”

About retinitis pigmentosa (RP)

Retinitis pigmentosa (RP) is a group of inherited retinal diseases caused by mutations in more than 100 different genes. The mutations cause photoreceptors to degenerate, leading to vision loss that typically begins with night blindness and progresses irreversibly, leaving many patients legally blind by middle age. RP is the most common inherited retinal disease, affecting about 1 in 4,000 people, or more than 1.5 million people worldwide.[2] There is currently no approved treatment for most people with RP.

The abstract for the article, titled “Optogenetic Therapy for Restoring Aspects of Visual Function”, is available on this link. Access to the full article requires an account to be created.

[1] GS030 has not received marketing authorization in any jurisdiction.

[2] Suleman N. Current understanding on Retinitis Pigmentosa: a literature review. Front Ophthalmol. 2025;5:1600283 (DOI:10.3389/fopht.2025.1600283)

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