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Study on the Safety and Effectiveness of RGN-259 Eye Drops for Patients with Neurotrophic Keratopathy

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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 Neurotrophic Keratopathy, which affects the eyes. It is a disease where the cornea, the clear front part of the eye, loses its sensitivity and ability to heal properly. The treatment being tested in this study is an eye drop solution called Timbetasin acetate ophthalmic solution 0.1%, also known by its code name RGN-259. This solution is designed to help heal the cornea and improve eye health.

The purpose of the study is to compare the safety and effectiveness of RGN-259 with a placebo, which looks like the real treatment but does not contain the active ingredient. Participants in the study will be randomly assigned to receive either the RGN-259 eye drops or the placebo. The study is conducted in a way that neither the participants nor the researchers know who is receiving the actual treatment, which helps ensure unbiased results.

Throughout the study, participants will use the eye drops for a period of up to four weeks. They will have regular check-ups to monitor the healing of their corneal defects and to assess any changes in their eye condition. The study aims to determine if the RGN-259 eye drops can effectively heal the cornea and improve symptoms associated with Neurotrophic Keratopathy.

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 visit and screening

    Upon joining the study, you will attend an initial visit. During this visit, your eligibility for the trial will be confirmed. This involves checking your medical history and current health status.

    You will undergo an eye examination to confirm the presence of a persistent epithelial defect in one or both eyes. This is a condition where the surface of the eye does not heal properly.

    Your eye sensitivity will be measured using a tool called the Cochet-Bonnet aesthesiometer. This tool gently touches the eye to assess how sensitive it is.

    A vision test will be conducted to measure your best corrected visual acuity (BCVA), which is how well you can see with the best possible glasses or contact lenses.

  2. Step 2

    Randomization and treatment assignment

    After confirming eligibility, you will be randomly assigned to receive either the RGN-259 ophthalmic solution or a placebo. The placebo looks the same as the RGN-259 solution but does not contain the active ingredient.

    This process is double-masked, meaning neither you nor the study staff will know which treatment you are receiving to ensure unbiased results.

  3. Step 3

    Treatment administration

    You will be instructed to apply the assigned eye drops to the affected eye(s) as directed. The dosage is 0.1% solution, and the frequency and duration will be specified by the study team.

    It is important to follow the instructions carefully and attend all scheduled visits to monitor your progress.

  4. Step 4

    Follow-up visits

    You will have several follow-up visits throughout the study. These visits are crucial for monitoring the healing of the eye defect and assessing any changes in your condition.

    During these visits, the size of the eye defect will be measured using a special dye called fluorescein that highlights the defect under a blue light.

    Your eye sensitivity and vision will be re-evaluated, and any side effects or changes in your health will be recorded.

  5. Step 5

    Final assessment

    At the end of the study period, a final assessment will be conducted. This includes a comprehensive eye examination to determine the overall healing of the eye defect.

    The study team will review all collected data to evaluate the safety and effectiveness of the treatment.

Who can join the trial?

10 criteria

  • Be male or female of any race, at least 18 years old.
  • Male participants must agree to use an adequate method of birth control.
  • Have provided written consent to participate in the study.
  • Be able and willing to follow instructions, including attending all study assessments and visits.
  • At the time of the first visit, have a Persistent Epithelial Defect (PED) in one or both eyes. This means a corneal defect that has not healed after 1 week of standard treatment, which includes using non-preserved eye lubricants, antibiotics, oral doxycycline, patching, amniotic membrane, serum tears, and/or therapeutic contact lenses. If you have been re-screened, you need to go through 1 week of standard treatment again right before the first visit.
  • Have stage 2 or 3 neurotrophic keratopathy in at least one eye, where the longest part of the defect is at least 1 mm. This must be confirmed by the study doctor not to be just superficial punctate keratitis at the first visit.
  • Have evidence of decreased corneal sensitivity, which means a reduced feeling in the cornea, measured as 40 mm or less using a tool called the Cochet-Bonnet aesthesiometer at the first visit.
  • Have a BCVA score of 75 letter counts or less in the study eye based on the ETDRS protocol. BCVA stands for Best Corrected Visual Acuity, which is a measure of the best vision you can achieve with glasses or contact lenses.
  • Have at least one eye that meets all the criteria mentioned in points 4, 5, 6, and 7 above.
  • Female participants who can have children must not be breastfeeding and must use and agree to continue using an acceptable method of birth control for at least 4 weeks before the first dose of the study product and until 12 weeks after the last dose. They must also have a negative urine pregnancy test during screening.

Who cannot join the trial?

3 criteria

  • Patients who are not diagnosed with Neurotrophic Keratopathy cannot participate.
  • Patients who are younger than 18 years old cannot participate.
  • Patients who are part of a vulnerable population, such as those unable to give consent, cannot participate.
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Investigated drugs

RGN-259 is an eye drop solution being tested for its ability to help heal the surface of the eye in people with a condition called Neurotrophic Keratopathy. This condition affects the cornea, which is the clear front part of the eye, and can lead to vision problems if not treated. The medication is designed to promote healing and reduce damage to the cornea by supporting the natural repair processes of the eye. In this clinical trial, researchers are studying how safe and effective RGN-259 is compared to a placebo, which is a substance with no active ingredients.

What is already known about the treatment

RGN-259 – RGN-259 is an eye drop solution administered directly to the eyes, designed to treat a condition called Neurotrophic Keratopathy, which affects the cornea. Currently, it is being studied in clinical trials to determine its safety and effectiveness compared to a placebo. The main therapeutic use of RGN-259 is to help heal and protect the cornea in patients with this condition. At the molecular level, it works by promoting cell growth and repair, which helps in healing the damaged corneal tissue. RGN-259 is classified as an ophthalmic solution, which means it is a medication specifically formulated for use in the eyes.

Investigated diseases

Neurotrophic Keratopathy – Neurotrophic Keratopathy is a degenerative disease of the cornea caused by impaired corneal innervation. It leads to a reduction or loss of corneal sensitivity, which can result in persistent epithelial defects and corneal ulcers. The disease progresses through stages, starting with superficial punctate keratopathy, advancing to persistent epithelial defects, and potentially leading to corneal ulcers and perforation. The lack of sensation in the cornea means that patients may not feel pain or discomfort, even as the condition worsens. Over time, the corneal surface becomes more vulnerable to injury and infection due to the impaired healing process. The progression of the disease can lead to significant visual impairment if not managed appropriately.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2022-502697-16-00Protocol codeSEER-3Estimated enrolment70 patientsSponsorRegentree LLC

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