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A study testing lenadogene nolparvovec gene therapy injections into the eye to improve vision in patients with ND4 Leber Hereditary Optic Neuropathy

InvestigationalNo placebo
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What is this trial about?

A plain-language summary of the goals, design and what participants do

This study involves patients with Leber Hereditary Optic Neuropathy, a condition that affects vision and is caused by changes in the mitochondrial NADH Dehydrogenase 4 gene, also known as the ND4 gene. This condition leads to vision loss because it affects the nerve that carries visual information from the eye to the brain. The treatment being tested is called Lumevoq, which is also known by its code name GS010. This treatment contains lenadogene nolparvovec, which is a type of gene therapy that uses a modified virus to deliver a working copy of the ND4 gene directly into the eye. The medicine is given as an intravitreal injection, which means it is injected into the gel-like substance inside the eye.

The purpose of this study is to find out how well two different dose levels of GS010 work in improving vision and how the retina, which is the light-sensitive layer at the back of the eye, functions after treatment. The study will look at changes in visual sharpness, which is measured using something called best corrected visual acuity, and will compare the results between patients receiving a higher dose and those receiving a lower dose. Patients in this study will receive injections in both eyes and will be followed for one and a half years after treatment to see how their vision changes over time.

During the study, patients will attend regular visits where their vision will be tested and their eyes will be examined to check for any side effects or problems. The study will also monitor for specific eye-related issues such as inflammation inside the eye and increases in eye pressure, as well as any other side effects that may occur. Images of the eye will be taken using a technique called optical coherence tomography to help doctors assess the condition of the retina and optic nerve throughout the study period.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial assessment and treatment preparation

    Your baseline vision will be measured using the best corrected visual acuity test, which determines how well you can see with corrective lenses. This measurement uses the LogMAR scale, a standardized chart for measuring vision.

    Images of your eyes will be taken using optical coherence tomography, a non-invasive imaging technique that creates detailed pictures of the back of your eye.

    A thorough examination of your eyes will be performed to ensure the media inside your eyes are clear and your pupils can be dilated properly.

  2. Step 2

    Treatment day

    You will receive an injection of lenadogene nolparvovec (also called GS010 or Lumevoq) into both of your eyes. This is called an intravitreal injection, which means the medication is injected directly into the gel-like substance inside your eye.

    The study will assign you to receive either a higher dose or a lower dose of the medication. This assignment is randomized, meaning it is determined by chance, similar to flipping a coin.

    The medication is a solution for injection designed to target the specific genetic mutation causing your vision loss.

  3. Step 3

    Follow-up monitoring period

    You will attend multiple follow-up visits over a period of 1.5 years after receiving the treatment.

    At each visit, your vision will be tested using the same best corrected visual acuity measurements to track any changes from your baseline.

    Your eyes will be examined for any side effects, with particular attention to inflammation inside the eye and increased eye pressure.

    If inflammation or increased eye pressure occurs, appropriate treatment with corticosteroids or pressure-lowering medications may be provided.

    Additional imaging of your eyes will be performed at scheduled intervals to monitor the health of your retina and optic nerve.

  4. Step 4

    Safety monitoring

    Throughout the study period, any side effects affecting your eyes will be recorded and assessed for their severity.

    Any side effects affecting other parts of your body will also be monitored and documented.

    If you are a woman of childbearing potential, you must use effective birth control methods for up to 6 months after receiving the treatment.

    If you are a male, you must use condoms with female partners for up to 6 months after receiving the treatment.

  5. Step 5

    Final assessment

    At the end of the 1.5-year follow-up period, a comprehensive evaluation of your vision will be performed to determine if there has been any improvement compared to your baseline measurements.

    The study will specifically look for an improvement of at least 0.2 LogMAR units on the vision scale, which represents a clinically meaningful change in visual acuity.

    All collected data regarding your vision changes and any side effects experienced during the study will be analyzed.

Who can join the trial?

11 criteria

  • You must be 15 years of age or older at the time when you first experienced vision loss
  • You must be willing and able to follow the study rules, attend all scheduled visits, and complete all required tests and examinations
  • You must provide written agreement to participate in the study. If you are under 18 years old, your parent or legal guardian must also provide written agreement
  • You must have vision loss in both eyes caused by a specific genetic condition called ND4 LHON, which is a hereditary eye disease that affects the nerve connecting the eye to the brain
  • Your vision must be at a certain level or better in both eyes when measured on a special vision chart. Specifically, your best corrected visual acuity (the best vision you can achieve with glasses or contact lenses) must be at least LogMAR +2.39
  • You must have genetic test results showing that you have a harmful change in a specific gene called the ND4 mitochondrial gene, and you must not have other harmful genetic changes that could cause damage to the eye nerve or retina. Previous genetic test results can be used if approved
  • The vision loss in your first affected eye must have started between 6 months and 1.5 years before joining the study
  • It must be possible to take clear images of the inside of both of your eyes using a special imaging technique called OCT (a scanning device that takes pictures of the back of the eye)
  • The clear parts of your eyes must be transparent enough, and your pupils must be able to open wide enough, to allow a complete eye examination
  • You must test negative for HIV (a virus that affects the immune system)
  • If you are a woman who can become pregnant, you must agree to use effective birth control methods for up to 6 months after receiving the treatment. If you are a man, you must agree to use condoms with female partners for up to 6 months after receiving the treatment

Who cannot join the trial?

1 criterion

  • No specific exclusion criteria have been provided in the available study information. Please consult with the study team or your doctor to learn about any conditions or situations that might prevent you from participating in this clinical trial.
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Investigated drugs

GS010 is an investigational gene therapy given as an injection into the eye (intravitreal injection). It is being studied to treat a specific genetic eye condition called ND4 Leber Hereditary Optic Neuropathy, which affects vision due to problems with the energy-producing parts of cells in the retina. The treatment aims to improve visual acuity (how clearly you can see) and help the mitochondria (the energy centers) in the retinal cells work better. In this study, patients receive injections in both eyes.

What is already known about the treatment

GS010 – GS010 is an experimental gene therapy medication administered through an intravitreal injection, which means it is injected directly into the eye. This treatment is currently being studied in clinical trials for patients with Leber Hereditary Optic Neuropathy caused by mutations in the ND4 gene, a rare inherited condition that leads to vision loss. The medication works at the molecular level by delivering genetic material to cells in the retina to help restore the function of damaged mitochondria, which are the energy-producing structures in cells. GS010 belongs to the class of gene therapy medications designed to correct specific genetic defects and improve visual function in affected patients.

Investigated diseases

Leber Hereditary Optic Neuropathy – Leber Hereditary Optic Neuropathy is an inherited eye condition that affects the optic nerve, which transmits visual information from the eye to the brain. This disease is caused by mutations in genes found in mitochondria, the energy-producing parts of cells. In this particular form, the mutation occurs in the NADH Dehydrogenase 4 gene. The condition typically begins with sudden vision loss in one eye, followed weeks or months later by vision loss in the other eye. The vision loss is usually painless and progresses rapidly over several weeks to months. This leads to severe reduction in sharpness of vision and difficulties in seeing colors, particularly affecting central vision needed for tasks like reading and recognizing faces.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IITrial ID2025-523339-20-00Protocol codeGS-LHON-CLIN-08Estimated enrolment14 patientsSponsorGensight Biologics

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