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Study on Long-Term Safety of Fazirsiran for Patients with Alpha-1 Antitrypsin Deficiency-Related Liver 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 Alpha-1 Antitrypsin Deficiency-Associated Liver Disease. This is a genetic disorder that can lead to liver problems due to a lack of a protein called alpha-1 antitrypsin, which is important for protecting the liver. The treatment being studied is a medication called Fazirsiran, also known by its code name TAK-999. Fazirsiran is a solution for injection that is designed to target specific liver cells to help manage this condition.

The purpose of this study is to evaluate the long-term safety and effectiveness of Fazirsiran in people with Alpha-1 Antitrypsin Deficiency-Associated Liver Disease. Participants in this study will receive Fazirsiran through subcutaneous injections, which means the medication is injected under the skin. The study will monitor participants over a period of time to observe any changes in their health and to ensure the treatment is safe and well-tolerated.

Throughout the study, participants will have regular check-ups to assess their liver health and overall well-being. This includes monitoring vital signs, conducting laboratory tests, and evaluating liver function. The study aims to provide valuable information on how Fazirsiran can help manage liver disease associated with Alpha-1 Antitrypsin Deficiency over an extended period.

The research process

The trial runs in 6 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 is designed to evaluate the long-term safety and effectiveness of fazirsiran for individuals with liver disease associated with alpha-1 antitrypsin deficiency.

  2. Step 2

    Initial assessment

    An initial assessment will be conducted to establish your baseline health status. This may include physical examinations, blood tests, and other necessary evaluations to ensure you meet the study criteria.

  3. Step 3

    Receiving fazirsiran

    You will receive fazirsiran as a solution for injection. The medication is administered through a subcutaneous injection, which means it is injected under the skin. The frequency and dosage will be determined by the study protocol and your healthcare provider.

  4. Step 4

    Regular follow-up visits

    You will have regular follow-up visits scheduled every 12 weeks. During these visits, your health will be monitored through various tests and assessments to track any changes or side effects.

  5. Step 5

    Ongoing monitoring

    Throughout the study, your vital signs, liver function, and overall health will be closely monitored. This includes regular blood tests and possibly liver biopsies to assess any changes in liver condition.

  6. Step 6

    End of study evaluation

    At the end of the study, a final evaluation will be conducted to assess the long-term effects of fazirsiran on your health. This will include a comprehensive review of all collected data and any changes in your condition.

Who can join the trial?

9 criteria

  • The participant must have been part of a previous study related to Alpha-1 Antitrypsin Deficiency-Associated Liver Disease.
  • Participants with fibrosis (a condition where the liver becomes scarred) from the AROAAT2001 study can join this study after their next scheduled visit every 12 weeks.
  • Participants with fibrosis who have completed the AROAAT2001 study can join this study.
  • Participants from the AROAAT2002 study in Cohorts 1 and 1b can join after completing the 24-week main study period.
  • Participants from Cohort 2 of the AROAAT2002 study can join after completing the 48-week main study period.
  • Participants who have completed the AROAAT2002 study can join this study.
  • If the first dose of the study treatment is delayed by more than 24 weeks after the last dose in the previous studies, the situation should be discussed with the medical monitor.
  • Participants can be of any gender.
  • The study includes participants from vulnerable populations, which means people who might need special protection or care.

Who cannot join the trial?

7 criteria

  • Patients who have a different liver disease not related to **Alpha-1 Antitrypsin Deficiency**. This is a specific condition where the liver is affected due to a lack of a protein called alpha-1 antitrypsin.
  • Patients who are not within the specified age range for the study. The study is open to certain age groups only.
  • Patients who are not able to follow the study procedures or take the study medication as required.
  • Patients who have other serious health conditions that might interfere with the study or make it unsafe for them to participate.
  • Patients who are pregnant or breastfeeding, as the effects of the study medication on unborn babies or infants are not known.
  • Patients who are participating in another clinical trial at the same time, as this could affect the results of the study.
  • Patients who have a history of allergic reactions to similar medications or any of the ingredients in the study medication.
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Investigated drugs

Fazirsiran is a medication being studied for its potential to help people with a condition called Alpha-1 Antitrypsin Deficiency-Associated Liver Disease. This condition affects the liver and can lead to serious health problems. Fazirsiran is designed to work by reducing the amount of a harmful protein that builds up in the liver due to this condition. The goal of the study is to see if Fazirsiran is safe to use over a long period and to understand how well it works in helping people with this liver disease.

What is already known about the treatment

Fazirsiran – Fazirsiran is administered as an injection, typically given under the skin. It is currently being studied in clinical trials, specifically in a Phase 3 study, to assess its long-term safety and effectiveness for treating liver disease associated with Alpha-1 Antitrypsin Deficiency (AATD). The main therapeutic use of Fazirsiran is to help manage liver disease caused by this genetic condition. At the molecular level, Fazirsiran works by reducing the production of abnormal proteins that can accumulate in the liver and cause damage. It is classified as a gene-silencing medication, which means it helps to decrease the expression of specific genes that lead to disease symptoms.

Investigated diseases

Alpha-1 Antitrypsin Deficiency-Associated Liver Disease – This disease is caused by a genetic deficiency of the protein alpha-1 antitrypsin, which is primarily produced in the liver. The deficiency leads to the accumulation of abnormal protein in the liver cells, causing liver damage. Over time, this can result in liver inflammation and scarring, known as fibrosis. As the disease progresses, it may lead to cirrhosis, where the liver becomes severely scarred and its function is impaired. The condition can also cause portal hypertension, which is increased blood pressure in the portal vein system. The progression of liver damage varies among individuals, and some may experience more severe liver complications than others.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2023-503497-21-00Protocol codeTAK-999-3003Estimated enrolment36 patientsSponsorTakeda Development Center Americas Inc.

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