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Study on Long-Term Safety of Eplontersen for Adults with Transthyretin-Mediated Amyloid Cardiomyopathy

Verified siteRegistered drugNo placebo
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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 Transthyretin-Mediated Amyloid Cardiomyopathy (ATTR-CM). This is a heart condition where abnormal proteins build up in the heart, affecting its function. The study will use a treatment called Eplontersen, which is also known by its code name ION 682884. Eplontersen is a type of medication called an antisense oligonucleotide, which is designed to target and reduce the production of specific proteins in the body. The purpose of this study is to evaluate the long-term safety of Eplontersen in patients with ATTR-CM.

Participants in the study will receive Eplontersen through a subcutaneous injection, which means it is injected under the skin. The study will also involve taking Concavit Capsules, which contain a combination of vitamins such as Vitamin A and Ascorbic Acid (Vitamin C). These capsules are taken orally, meaning they are swallowed. The study will last for a period of up to 36 months, during which participants will be monitored regularly to assess the safety and tolerability of the treatment. This includes checking various health indicators through blood tests and other clinical assessments.

The study aims to gather information on how the treatment affects the body over time, including any side effects or changes in health status. Participants will be asked to complete questionnaires about their quality of life and undergo tests to measure heart function and other health markers. The results of this study will help determine the long-term safety of Eplontersen for people with ATTR-CM.

The research process

The trial runs in 7 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, you will be informed about the purpose and procedures involved. This study aims to assess the long-term safety of eplontersen in patients with transthyretin-mediated amyloid cardiomyopathy (ATTR-CM).

    You will be required to have completed a previous study or have a diagnosis of ATTR-CM and satisfactory participation in a related study, as determined by the investigator.

  2. Step 2

    Medication administration

    You will receive eplontersen as a solution for injection. This will be administered through a subcutaneous injection, which means it is injected under the skin.

    The frequency and dosage of the medication will be determined by the study protocol and the investigator overseeing your participation.

  3. Step 3

    Vitamin A supplementation

    As part of the study, you will be required to adhere to a vitamin A supplementation regimen. This is to ensure your safety and the effectiveness of the treatment.

  4. Step 4

    Regular health assessments

    Throughout the study, you will undergo regular health assessments. These will include laboratory tests, physical examinations, and electrocardiograms (ECGs) to monitor your health and the effects of the medication.

    The assessments will focus on various health indicators such as platelet count, kidney function, liver function, thyroid function, and coagulation tests.

  5. Step 5

    Monitoring side effects

    You will be monitored for any side effects or adverse reactions to the medication. This includes tracking any unexpected symptoms or changes in your health.

    The study will also assess the presence of any anti-drug antibodies, which are immune responses that can occur with certain medications.

  6. Step 6

    Biomarker and clinical tests

    The study will involve analysis of various biomarkers and clinical tests over time. Biomarkers are substances in your body that can indicate how well your body is responding to the treatment.

    Tests will include measurements of transthyretin serum levels, walking tests, echocardiograms, and quality of life questionnaires.

  7. Step 7

    Completion of the study

    The study is expected to continue until August 2029. Your participation will involve regular visits and assessments as outlined in the study protocol.

    Upon completion, you will have a final assessment to evaluate your overall health and the long-term effects of the treatment.

Who can join the trial?

5 criteria

  • Must have completed the Treatment Period and the End of Treatment Visit of the previous study (ION-682884-CS2) OR have a diagnosis of Transthyretin-Mediated Amyloid Cardiomyopathy (ATTR CM) and satisfactory participation in the ISIS 420915CS101 study, as judged by the study doctor and sponsor.
  • The study doctor must be willing to treat the participant with open label ION-682884 (eplontersen).
  • Must be willing to take vitamin A supplements as required by the study protocol.
  • Both men and women can participate.
  • Participants must be within the specified age range for the study.

Who cannot join the trial?

9 criteria

  • Patients who have a different heart condition other than Transthyretin-Mediated Amyloid Cardiomyopathy (ATTR CM) cannot participate.
  • Patients who are not within the specified age range for the study cannot participate.
  • Patients who are not able to follow the study procedures or take the study medication as required cannot participate.
  • Patients who have any other serious medical conditions that might interfere with the study cannot participate.
  • Patients who are pregnant or breastfeeding cannot participate.
  • Patients who have participated in another clinical trial recently may not be eligible.
  • Patients who have allergies to the study medication or its ingredients cannot participate.
  • Patients who have a history of substance abuse or alcohol abuse cannot participate.
  • Patients who have any condition that the study doctors believe would make it unsafe for them to participate cannot participate.
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Investigated drugs

Eplontersen is a medication being studied for its long-term safety in patients with a condition called transthyretin-mediated amyloid cardiomyopathy, or ATTR-CM. This condition affects the heart and can lead to heart failure. Eplontersen is designed to help manage this condition by targeting and reducing the production of a specific protein that contributes to the disease. The goal of using Eplontersen in this trial is to see how well patients tolerate the medication over an extended period and to ensure it is safe for long-term use.

What is already known about the treatment

Eplontersen – Eplontersen is administered as an injection, typically under the skin, and is currently being studied for its long-term safety in treating a heart condition called Transthyretin-Mediated Amyloid Cardiomyopathy (ATTR-CM). This medication is still under investigation, and its primary purpose is to assess its safety and tolerability over extended use. Eplontersen works by targeting and reducing the production of a specific protein that can build up and cause damage in the heart. It belongs to a class of drugs known as antisense oligonucleotides, which are designed to interfere with the genetic instructions that produce harmful proteins.

Investigated diseases

Transthyretin-Mediated Amyloid Cardiomyopathy (ATTR-CM) – This disease is characterized by the buildup of abnormal protein deposits called amyloid in the heart tissue. These deposits are formed from transthyretin, a protein that normally transports thyroid hormones and vitamin A in the blood. Over time, the accumulation of amyloid disrupts the normal structure and function of the heart, leading to thickening and stiffening of the heart walls. This results in impaired heart function, which can cause symptoms such as fatigue, shortness of breath, and swelling in the legs. The disease progresses as the amyloid deposits continue to accumulate, further compromising heart function. It is a rare condition that can be hereditary or occur without a family history.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2022-502415-11-00Protocol codeION-682884-CS12Estimated enrolment1 254 patientsSponsorIonis Pharmaceuticals Inc.

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