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Study on Fazirsiran for Patients with Alpha-1 Antitrypsin Deficiency Liver Disease and Mild Fibrosis

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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, which is a genetic disorder that can lead to liver damage. The study is investigating a treatment called Fazirsiran, also known by its code name TAK-999. Fazirsiran is a type of medication designed to target specific genes in the liver to help reduce the damage caused by this disease. The trial will compare the effects of Fazirsiran with a placebo to understand its safety and effectiveness, particularly in people with mild liver scarring, also known as fibrosis.

The main goal of the study is to evaluate the long-term safety of Fazirsiran, with a special focus on lung health, as the condition can also affect the lungs. Participants in the study will receive either Fazirsiran or a placebo through injections. The study will monitor various health indicators, including lung function and liver health, over a period of time to see how the treatment affects these areas. Participants will undergo regular check-ups and tests to track any changes in their condition.

This study is important for understanding how Fazirsiran can help people with Alpha-1 Antitrypsin Deficiency-Associated Liver Disease and to ensure that it is safe for long-term use. By participating in this trial, researchers hope to gather valuable information that could lead to better treatment options for those affected by this genetic disorder.

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 participant is confirmed to have a diagnosis of the PiZZ genotype associated with alpha-1 antitrypsin deficiency. The participant is between 18 and 75 years old and has evidence of mild liver scarring, known as METAVIR stage 1 fibrosis, confirmed by a liver biopsy.

  2. Step 2

    Initial assessment

    An initial assessment is conducted to evaluate the participant's lung function and overall health status. This includes checking vital signs, performing an electrocardiogram (ECG), and conducting laboratory tests such as blood and urine analysis.

  3. Step 3

    Treatment phase

    The participant receives either the study medication, fazirsiran, or a placebo. The medication is administered as a subcutaneous injection, which means it is injected under the skin. The frequency and dosage are determined by the study protocol.

  4. Step 4

    Ongoing monitoring

    Throughout the study, the participant's health is monitored regularly. This includes checking for any side effects, changes in lung function, and liver health. Pulmonary function tests and computed tomography (CT) scans are performed to assess lung density and function over time.

  5. Step 5

    Final assessment

    At the end of the study, a final assessment is conducted. This includes a comprehensive evaluation of the participant's lung and liver health, as well as any changes in the levels of specific proteins associated with the condition.

Who can join the trial?

4 criteria

  • The participant must have a diagnosis of the **PiZZ genotype AATD**. This means they have a specific genetic form of Alpha-1 Antitrypsin Deficiency.
  • The participant, of any sex, is aged **18 to 75 years**, inclusive.
  • The participant has evidence of **METAVIR stage 1 liver fibrosis**. This is a mild form of liver scarring, which is checked by a liver biopsy, a procedure where a small piece of the liver is taken to look for disease.
  • The participant has a **pulmonary status** meeting the protocol's requirements. This means their lung health must meet certain standards set by the study.

Who cannot join the trial?

7 criteria

  • Patients with other serious liver diseases that are not related to **Alpha-1 Antitrypsin Deficiency**.
  • Patients who have had a liver transplant.
  • Patients with severe lung diseases that are not related to **Alpha-1 Antitrypsin Deficiency**.
  • Patients who are currently participating in another clinical trial.
  • Patients who have a history of drug or alcohol abuse.
  • Patients who are pregnant or breastfeeding.
  • Patients who have any condition that the study doctors believe would make it unsafe for them to participate.
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Investigated drugs

Fazirsiran is a medication being studied for its potential to treat liver disease associated with Alpha-1 Antitrypsin Deficiency. This condition can lead to liver damage due to the accumulation of abnormal proteins. Fazirsiran aims to reduce these harmful proteins in the liver, potentially improving liver function and slowing disease progression. The trial is also focused on assessing the long-term safety of Fazirsiran, particularly its effects on lung health and pulmonary function.

What is already known about the treatment

Fazirsiran – Fazirsiran is administered as an injection, typically under the skin. It is currently being studied in clinical trials, specifically in a Phase 3 study, to assess its safety and effectiveness for treating liver disease associated with Alpha-1 Antitrypsin Deficiency. The main therapeutic indication for Fazirsiran is to address liver damage caused by this genetic condition. At the molecular level, Fazirsiran works by reducing the production of abnormal alpha-1 antitrypsin protein, which can accumulate and cause liver damage. It is classified pharmacologically as an RNA interference therapeutic, targeting specific genetic material to prevent disease progression.

Investigated diseases

Alpha-1 Antitrypsin Deficiency-Associated Liver Disease – This is a genetic condition where the liver produces an abnormal form of a protein called alpha-1 antitrypsin. This abnormal protein can accumulate in the liver, leading to liver damage over time. The disease may start with mild liver dysfunction and can progress to more significant liver issues. Symptoms can include jaundice, fatigue, and abdominal swelling. The progression of the disease varies among individuals, with some experiencing more severe liver problems than others. It is considered a rare disease, affecting a small percentage of the population.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2023-504198-19-00Protocol codeTAK-999-3002Estimated enrolment50 patientsSponsorTakeda Development Center Americas Inc.

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