RecruitingOBSERVATIONAL

Long-term Safety of Eplontersen Treated aTTR Patients and in Liver Transplant and Severely Hepatic Impaired Subpopulations

This study is checking the long-term safety of a medicine called eplontersen for people with a rare condition called transthyretin amyloidosis (ATTR). This condition can affect different parts of the body, like the heart or nerves. The study is important because it’s looking at information we don't have yet about how safe eplontersen is over a longer time. Researchers are particularly interested in people who have had a liver transplant or have severe liver problems, as these groups of patients might react differently to the medication. It's an observational study, which means people aren't given a new treatment. Instead, researchers are simply collecting information from patients who are already taking eplontersen to understand its effects, including any side effects or changes in their health over time.

At a glance

Status

Recruiting

Sponsor

AstraZeneca

Enrolment target

320

Start

01 Sep 2026

Estimated completion

29 Jan 2032

Transthyretin Amyloidosis Transthyretin Amyloidosis With Cardiomyopathy Transthyretin Amyloidosis With Polyneuropathy

What is this study about?

This study is about a medicine called eplontersen, which is used to treat a rare condition called transthyretin amyloidosis, or ATTR for short. ATTR happens when a specific protein builds up in the body's organs and tissues, like the heart or nerves, causing problems. There are different types, including those affecting the heart (cardiomyopathy) or nerves (polyneuropathy).

This is an "observational study." This means that the researchers aren't giving people a new treatment or asking them to change anything they are already doing. Instead, they are carefully watching and collecting information from people who are already taking eplontersen. The main goal is to understand how safe the medicine is over a long time. They want to see if people develop any new health issues, unusual test results, or serious side effects while taking eplontersen.

A key part of this study is looking specifically at how eplontersen affects two particular groups of patients: those who have had a liver transplant in the past, and those who have severe liver problems. Currently, there isn't much information about how eplontersen works in these groups, so the study aims to fill these gaps. By gathering this information, doctors can better understand who might benefit most from eplontersen and how to use it safely for all patients with ATTR.

Key takeaways

This study is about the long-term safety of eplontersen for people with ATTR.
It's an 'observational' study – researchers collect information, you don't take new medication.
It specifically looks at patients with previous liver transplants or severe liver issues.
The goal is to understand any long-term side effects or health changes.
Your medical care won't change if you participate; it helps future patients.

Who may be eligible?

To be part of this study, you would first need to have taken part in a main study (called D8450R00003) where you agreed for your health information to be used for future research. You also need to be an adult, aged 18 or older, with a confirmed diagnosis of ATTR.

Crucially, you should have started taking eplontersen no more than one year before joining this particular study. If you're not taking eplontersen but started a different ATTR treatment during the main study's observation period, you might also be included to help compare information.

However, you wouldn't be able to join if you started taking eplontersen more than one year before this study started. Also, if you took part in a different ATTR treatment study that involved a specific intervention (like a new drug or procedure) within the last year, you would not be eligible.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you 18 years old or older?
Do you have a confirmed diagnosis of transthyretin amyloidosis (ATTR)?
Have you already been taking eplontersen for less than a year?
Did you previously agree for your health data from the D8450R00003 study to be used for future research?

Answer every question to see your result.

What does participation involve?

This is an observational study, so you wouldn't be asked to do anything new. You will continue to take eplontersen as prescribed by your doctor. The study involves collecting information from your medical records from when you started eplontersen and continuing to monitor your health over time. This includes information about your general health, any new medical conditions, results from blood tests, and any side effects you experience. Your doctors will continue to look after your health as usual. The researchers will simply gather this information from your routine care. The data collection for this study is expected to last from late 2026 until early 2032, with a final report due in early 2033.

Potential risks and benefits

As this is an observational study, there are no direct medical benefits or risks from being in the study itself, as you would continue to receive your usual medical care. The benefit comes from helping researchers gather important information about the long-term safety of eplontersen, especially for patients with liver conditions or transplants. This knowledge can help improve care for many other patients with ATTR in the future. You always have the right to withdraw your consent for your data to be used at any time without affecting your medical treatment.

Locations (6)

Research Site
Verified postcode
Los Angeles, United States· Recruiting
Research Site
Verified postcode
Vancouver, Canada· Recruiting
Research Site
Verified postcode
Beijing, China· Recruiting
Research Site
Verified postcode
Hanover, Germany· Recruiting
Research Site
Verified postcode
Majadahonda, Spain· Recruiting
Research Site
Verified postcode
Birmingham, United Kingdom· Recruiting

Common questions

What is an observational study?

It means researchers watch and collect information about your health and treatment without asking you to do anything new or different.

Will I receive new treatment in this study?

No, this study does not involve new treatments. You will continue with your eplontersen treatment as prescribed by your doctor.

Why are they focusing on liver transplant patients?

There's not much information about how eplontersen affects people who've had liver transplants or have severe liver problems, so the study aims to understand this better.

How long will my information be collected?

Data collection for the study is planned to run from late 2026 until early 2032.

Can I leave the study if I change my mind?

Yes, you can withdraw your consent for your information to be used at any time, and it won't affect your medical care.

How to find out more

AstraZeneca Clinical Study Information Center

information.center@astrazeneca.com 1-877-240-9479 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.