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Study on the Safety and Tolerability of Teprotumumab for Patients with Thyroid Eye Disease

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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 known as Thyroid Eye Disease (TED). This is a condition where the muscles and tissues around the eyes become inflamed, often causing the eyes to bulge or become misaligned. The trial is testing a medication called Teprotumumab, which is given as an infusion, meaning it is delivered directly into the bloodstream through a vein. The study will also use a placebo, which is a solution that looks like the medication but does not contain the active ingredient.

The purpose of the study is to evaluate the safety and tolerability of different durations of treatment with Teprotumumab in patients with Thyroid Eye Disease. Participants will be randomly assigned to receive either the medication or the placebo. The study will monitor how patients respond to the treatment over time, including any side effects they may experience. The trial will also assess whether patients need to be treated again after the initial treatment period.

Throughout the study, participants will have regular check-ups to monitor their condition and the effects of the treatment. These check-ups will include measurements of eye symptoms and overall health assessments. The study aims to provide valuable information on how well Teprotumumab works for treating Thyroid Eye Disease and how long the treatment should last for the best results.

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, the patient will receive a detailed explanation of the trial's purpose and procedures. The patient must provide written informed consent to participate.

    The patient will be screened to ensure they meet the eligibility criteria, including age, health status, and specific conditions related to Thyroid Eye Disease.

  2. Step 2

    Initial treatment period

    The patient will begin the initial treatment period, which involves receiving the medication teprotumumab.

    Teprotumumab is administered as an infusion. The dosage and frequency will be determined based on the patient's weight and specific treatment plan.

    The patient will attend regular appointments to receive the infusion and to monitor their response to the treatment.

  3. Step 3

    Follow-up period

    After completing the initial treatment period, the patient will enter a follow-up period.

    During this time, the patient's condition will be monitored to assess the effectiveness of the treatment and to check for any side effects.

    The patient will continue to attend scheduled appointments for evaluations and assessments.

  4. Step 4

    Re-treatment period (if necessary)

    If the patient's condition requires further treatment, a re-treatment period may be initiated.

    The patient will receive additional doses of teprotumumab as needed, following the same infusion process.

    The patient's response to the re-treatment will be closely monitored.

  5. Step 5

    End of trial

    At the end of the trial, the patient's overall response to the treatment will be evaluated.

    The patient will receive a final assessment to determine the long-term effects of the treatment on their condition.

    The trial is expected to conclude by August 2025.

Who can join the trial?

10 criteria

  • Provide written informed consent, which means you agree to participate in the study after being informed about it.
  • Be willing and able to follow the treatment plan and attend all evaluations during the study.
  • Be a male or female between 18 and 80 years old at the time of screening.
  • Have been diagnosed with **Thyroid Eye Disease (TED)** within the last 7 years before screening.
  • Have **proptosis**, which means your eyes bulge out more than 3 millimeters from the baseline or more than 3 millimeters above normal for your race and gender, as estimated by your doctor.
  • Have your thyroid condition under control, meaning your thyroid hormone levels are not too high or too low, or only mildly so, at screening. Efforts should be made to correct any mild thyroid imbalances and maintain normal thyroid function during the study.
  • Do not need immediate eye surgery and are not planning any corrective eye surgery or radiation treatment during the study.
  • If you have diabetes, your **HbA1c** level, which is a measure of blood sugar control, should be 8.0% or lower at screening.
  • If you have a history of **Inflammatory Bowel Disease (IBD)**, such as ulcerative colitis or Crohn's disease, you must be in remission, meaning no active symptoms, for at least 3 months. You should not have had bowel surgery in the last 6 months and should not plan any surgery during the study. You can continue stable IBD treatments that haven't changed in the last 3 months.
  • If you are a woman who can become pregnant, you must have a negative pregnancy test at screening and at all specified times during the study. If you are sexually active with a male partner who hasn't had a vasectomy, you must agree to use two reliable forms of birth control during the study. One of these should be hormonal, like birth control pills, and should be started at least one full cycle before the study begins and continued for 180 days after the last dose of the study medication. Highly effective birth control methods include implants, injections, certain IUDs, a vasectomized partner, or sexual abstinence if it fits your lifestyle. Periodic abstinence or withdrawal methods are not acceptable.

Who cannot join the trial?

8 criteria

  • Patients who have other serious eye conditions that are not related to **Thyroid Eye Disease**.
  • Patients who have had previous surgery for **Thyroid Eye Disease**.
  • Patients who are currently receiving other treatments for **Thyroid Eye Disease**.
  • Patients with uncontrolled **diabetes**. **Diabetes** is a condition where the body has trouble managing blood sugar levels.
  • Patients with severe **heart disease**. **Heart disease** refers to various conditions that affect the heart's function.
  • Patients who are pregnant or breastfeeding.
  • Patients who have participated in another clinical trial within the last 30 days.
  • Patients with a history of **allergic reactions** to similar medications. **Allergic reactions** are when the body's immune system reacts to a substance as if it were harmful.
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Investigated drugs

Teprotumumab is a medication being studied for its effects on Thyroid Eye Disease (TED). This trial aims to evaluate how safe and tolerable the medication is when given for different lengths of time. The study also looks at whether patients might need to be treated again after the initial treatment period.

What is already known about the treatment

Teprotumumab – This medication is administered through intravenous infusion, meaning it is given directly into a vein. It is currently being studied in clinical trials for its safety and effectiveness in treating Thyroid Eye Disease, a condition that affects the eyes. Teprotumumab works by blocking a specific protein involved in the inflammation and swelling associated with this disease. It is classified as a monoclonal antibody, which is a type of drug designed to target and neutralize specific proteins in the body.

Investigated diseases

Thyroid Eye Disease – This condition is an autoimmune disorder that affects the muscles and other tissues around the eyes. It is often associated with an overactive thyroid gland, commonly due to Graves' disease. The disease can cause symptoms such as bulging eyes, redness, swelling, and discomfort. As it progresses, patients may experience double vision and difficulty moving the eyes. The severity of symptoms can vary, and in some cases, the disease may stabilize or improve over time. However, in other cases, it can lead to more significant eye problems if not managed properly.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase ITrial ID2024-515090-96-00Protocol codeHZNP-TEP-402Estimated enrolment295 patientsSponsorHorizon Therapeutics USA Inc.

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