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Study on the Effects of Bosentan for Patients with Early Stage Non-Arteritic Anterior Ischemic Optic Neuropathy

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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 the effects of a medication called bosentan in patients experiencing an eye condition known as acute non-arteritic anterior ischemic optic neuropathy (NAION). This condition affects the optic nerve, which is crucial for vision, and can lead to sudden vision loss. The trial aims to evaluate how bosentan, taken as a tablet, might help manage this condition during its early stages.

The study involves taking bosentan at a daily dose of 250 mg for two months. Participants will be randomly assigned to receive either the medication or a placebo. The main goal is to assess the impact of bosentan on the visual field, which is the area a person can see without moving their eyes, over a period of three months. The study will also look at other factors such as the thickness of the optic nerve fibers, visual clarity, and certain markers of inflammation in the body.

Throughout the study, participants will undergo various assessments to monitor changes in their vision and overall eye health. These assessments will include tests to measure visual acuity, which is the sharpness of vision, and the visual field. The study will also track blood pressure and other health indicators to ensure the safety and effectiveness of the treatment. The trial is expected to continue until December 2027, providing valuable insights into the potential benefits of bosentan for individuals with NAION.

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

    Upon joining the study, an initial assessment is conducted to confirm eligibility. This includes verifying age, pregnancy status for women, and blood pressure levels. A diagnosis of early stage acute non-arteritic anterior ischemic optic neuropathy (NOIAA) is required.

    A consent form must be signed, and participants should be affiliated with a social security scheme.

  2. Step 2

    Baseline measurements

    Baseline measurements are taken, including visual field tests and optic fiber layer thickness using SD OCT. Visual acuity is assessed using the ETDRS scale.

    Blood pressure readings are recorded for both daytime and nighttime.

  3. Step 3

    Medication administration

    Participants receive bosentan in the form of film-coated tablets. The dosage is 250 mg daily, administered orally.

    The treatment duration is 2 months.

  4. Step 4

    Follow-up assessments

    At 3 months, the effect of the medication on the visual field is evaluated. This involves measuring the average deficit in the automated visual field test.

    Secondary assessments include optic fiber layer thickness, visual acuity, and various inflammation biomarkers.

  5. Step 5

    Long-term monitoring

    Participants are monitored for up to 24 months to assess the rate of bilateralization of the contralateral eye and overall quality of life using a questionnaire.

    Additional tests may include plasma assays and further visual field evaluations.

Who can join the trial?

6 criteria

  • Men or women aged 50 or over
  • For women who are not yet in menopause, a negative pregnancy test is required, and they must use effective birth control during the study
  • Patients must have signed the consent form, which means they agree to participate in the study
  • Patients must be part of or have access to a social security system
  • Patients must have a systolic blood pressure (the top number in a blood pressure reading) of 100 mmHg or higher
  • The diagnosis of **NOIAA** (non-arteritic anterior ischemic optic neuropathy) should be recent, within 21 days, and include changes in the visual field. This may or may not be accompanied by a sudden, painless decrease in vision. There should also be swelling of the optic nerve head, which can be pale or white, and sometimes there may be small bleeding around the optic nerve. **Horton's disease** (another condition) should be ruled out

Who cannot join the trial?

8 criteria

  • Patients with any other eye disease that could affect vision.
  • Patients who have had eye surgery in the last 3 months.
  • Patients with a history of severe heart problems.
  • Patients who are currently taking medications that could interfere with the study drug.
  • Patients with severe liver or kidney disease.
  • Patients who are pregnant or breastfeeding.
  • Patients who have participated in another clinical trial in the last 30 days.
  • Patients with a known allergy to the study drug or similar medications.
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Investigated drugs

Bosentan is a medication being studied for its potential benefits in managing patients with a specific eye condition called non-arteritic acute anterior ischemic optic neuropathy (NOIAA). The trial aims to see if taking bosentan can improve the visual field, which is the area a person can see around them while looking straight ahead. The study is focused on understanding how bosentan might help patients during the early stages of this condition.

What is already known about the treatment

Bosentan – Bosentan is administered orally in tablet form and is currently being evaluated in clinical trials for its effects on early-stage acute non-arteritic anterior ischemic optic neuropathy. It is primarily used to treat pulmonary arterial hypertension, but its potential benefits in optic neuropathy are under investigation. Bosentan works by blocking endothelin receptors, which helps to relax blood vessels and improve blood flow. It is classified as an endothelin receptor antagonist.

Investigated diseases

Acute Non-Arteritic Anterior Ischemic Optic Neuropathy – This condition is characterized by sudden vision loss due to reduced blood flow to the optic nerve. It typically affects one eye and is not associated with inflammation of the arteries. The disease often presents with a painless, rapid decrease in vision, usually noticed upon waking. Patients may experience a partial or complete loss of vision in the affected eye, with the possibility of visual field defects. The optic disc may appear swollen during an eye examination. Over time, the swelling may subside, but some degree of vision loss often remains.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-518345-21-00Protocol code38RC12.228Estimated enrolment94 patientsSponsorCentre Hospitalier Universitaire Grenoble Alpes

sourced from the EU Clinical Trials Register and site verification

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