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Study on the Effectiveness and Safety of Ultevursen for Patients with Retinitis Pigmentosa Due to USH2A Gene Mutations

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What is this trial about?

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

This clinical trial is focused on studying a condition called Retinitis Pigmentosa, which is a genetic disorder that affects the eyes and can lead to vision loss. The study is specifically looking at cases of Retinitis Pigmentosa caused by changes in a part of a gene known as Exon 13 of the USH2A gene. The treatment being tested is a medication called Ultevursen, also known by its code name QR-421a. Ultevursen is a type of medicine known as an antisense oligonucleotide, which is designed to target specific genetic mutations.

The purpose of this study is to evaluate how effective and safe Ultevursen is for people with this specific type of Retinitis Pigmentosa. Participants in the study will receive either the Ultevursen treatment or a placebo, which is a procedure that mimics the treatment but does not contain the active medication. The study will last for two years, during which participants will receive regular injections of the treatment directly into the eye, a method known as intravitreal use. Throughout the study, participants will have their vision and eye health monitored to assess any changes or improvements.

The study aims to gather information on how Ultevursen affects the progression of Retinitis Pigmentosa over time. Researchers will look at various aspects of vision, such as changes in the retina's sensitivity and visual acuity, which is the clarity or sharpness of vision. The study will also monitor any side effects or adverse reactions to the treatment. This research is important for understanding how to better treat Retinitis Pigmentosa and potentially improve the quality of life for those affected by this condition.

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

    Joining the study

    Upon joining the study, participants are randomly assigned to either the treatment group or the sham group. The treatment group receives the active medication, ultevursen, while the sham group undergoes a procedure that mimics the injection but without actual medication administration.

  2. Step 2

    Treatment administration

    Participants in the treatment group receive ultevursen as a solution for injection. The medication is administered through an intravitreal injection, which means it is injected into the eye. The frequency and dosage of the injections are determined by the study protocol and are designed to evaluate the medication's effectiveness over a two-year period.

  3. Step 3

    Monitoring and assessments

    Throughout the study, participants undergo regular monitoring and assessments to evaluate the efficacy, safety, and tolerability of the treatment. These assessments include measuring changes in retinal sensitivity, visual acuity, and other vision-related parameters at specified intervals, such as months 12 and 24.

  4. Step 4

    Safety evaluations

    Safety evaluations are conducted to monitor any adverse events related to the treatment. This includes both ocular (eye-related) and non-ocular events. The presence of anti-drug antibodies against ultevursen is also assessed to ensure the treatment's safety.

  5. Step 5

    Completion of the study

    The study is designed to last for two years, with the primary objective of evaluating the treatment's efficacy after 24 months. Upon completion, participants may undergo final assessments to determine the overall impact of the treatment on their condition.

Who can join the trial?

14 criteria

  • Must be an adult (18 years or older) who can give permission to join the study, or a minor (8 to under 18 years) who can agree to join with a parent or guardian's written permission.
  • During the initial check, the difference in vision test results (BCVA letters) from two separate tests should be within 10 letters. If not, the study doctor will decide if the person can join.
  • Both eyes should have similar vision levels, meaning the average vision test result (BCVA) of one eye should be within 10 letters of the other eye. If not, the study doctor will decide if the person can join.
  • Must have reliable eye measurements as described in the study guide.
  • No significant eye problems that block vision or prevent good eye imaging, as checked by the study doctor.
  • Cannot be pregnant or breastfeeding. Women who can have children and men who can father children must use effective birth control methods. Women who cannot have children do not need to use birth control if they meet the study's entry rules.
  • Must be willing to follow the study rules, attend study visits, and complete all study tests. For minors, a parent or caregiver must also agree to follow the study rules and attend visits.
  • Both eyes must show signs of **Retinitis Pigmentosa (RP)**, which is a genetic eye condition, with or without hearing loss. The study doctor will confirm the type of RP during the initial check.
  • Must have a genetic diagnosis showing changes in the **USH2A gene**, with at least one change in a specific part of the gene. A past genetic test report is acceptable with approval.
  • Must have a clearly visible and measurable part of the eye (EZ width) of at least 2.5 mm in both eyes, as checked by a special eye scan (SD-OCT).
  • Must have a vision test result (BCVA) of at least 55 letters, which is similar to 20/80 vision on a standard eye chart.
  • Must have some vision field loss, with a sensitivity between 4 and 25 decibels (dB) using a specific test size.
  • Must have a sensitivity of more than 2 dB in a specific eye test (MP).
  • No issues that would prevent high-quality eye images from being taken in both eyes, as determined by the study doctor.

Who cannot join the trial?

4 criteria

  • Individuals who do not have a diagnosis of Retinitis Pigmentosa cannot participate. Retinitis Pigmentosa is a group of rare eye diseases that affect the retina, which is the light-sensitive tissue at the back of the eye.
  • Participants must be within certain age ranges. If you are not within these age ranges, you cannot participate.
  • Both males and females can participate, but if you do not identify as either, you may not be eligible.
  • If you are part of a vulnerable population, you may not be eligible. Vulnerable populations include groups that may have limited ability to give informed consent or are at higher risk of harm.
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Investigated drugs

Ultevursen is a medication being studied for its potential to treat Retinitis Pigmentosa, a genetic disorder that affects vision. This trial is specifically looking at its effects on patients with mutations in a specific part of a gene known as Exon 13 of the USH2A gene. The study aims to determine how effective, safe, and tolerable Ultevursen is over a period of two years.

What is already known about the treatment

Ultevursen – Ultevursen is administered through an injection directly into the eye, specifically targeting the retina. It is currently being studied in clinical trials for its potential to treat Retinitis Pigmentosa, a genetic disorder that affects vision. The medication is designed to work by addressing mutations in exon 13 of the USH2A gene, which are known to contribute to this condition. As a gene therapy, Ultevursen aims to modify or correct the genetic defects at the molecular level, potentially slowing or halting the progression of vision loss. It is classified under investigational gene therapies, with ongoing research to determine its efficacy and safety.

Investigated diseases

Retinitis Pigmentosa – Retinitis Pigmentosa is a group of genetic disorders that affect the retina's ability to respond to light, leading to a gradual loss of vision. It typically begins with night blindness, followed by a slow loss of peripheral vision, eventually leading to tunnel vision. As the disease progresses, individuals may experience difficulty seeing in low light conditions and a reduction in central vision. The condition is caused by mutations in various genes that are responsible for the health and function of the photoreceptor cells in the retina. Over time, these cells deteriorate and die, resulting in the characteristic vision loss associated with the disease. Retinitis Pigmentosa is considered a rare disease and can vary significantly in its progression and severity among individuals.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IITrial ID2024-515199-10-00Protocol codeSB-421a-006Estimated enrolment75 patientsSponsorLaboratoires Thea

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