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

Fast replyRegistered 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 Alpha-1 Antitrypsin Deficiency-Associated Liver Disease. This disease is linked to an abnormal version of a protein called alpha-1 antitrypsin, which can lead to liver damage and scarring, also known as fibrosis. The study is testing a treatment called Fazirsiran, which is a solution for injection. Fazirsiran is also known by its code name TAK-999 and is designed to target specific liver cells to help reduce the effects of this disease.

The purpose of the study is to evaluate how effective Fazirsiran is compared to a placebo in improving liver health in people with this condition. Participants in the study will receive either Fazirsiran or a placebo through subcutaneous injections, which means the injection is given under the skin. The study will take place over a period of time, with regular check-ups to monitor the health of the liver and the overall safety of the treatment.

Throughout the study, participants will undergo various assessments to track changes in their liver condition. These assessments will help determine if Fazirsiran can reduce liver scarring and improve liver function. The study aims to provide valuable information on whether this treatment can be a beneficial option for people with Alpha-1 Antitrypsin Deficiency-Associated Liver Disease.

The research process

The trial runs in 8 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial visit

    Upon joining the study, an initial visit is scheduled. During this visit, a detailed explanation of the study procedures, potential risks, and benefits is provided. Consent is obtained to participate in the trial.

    A comprehensive medical history is taken, and a physical examination is conducted to ensure eligibility based on the study criteria.

  2. Step 2

    Screening tests

    Screening tests are performed to confirm the diagnosis of Alpha-1 Antitrypsin Deficiency-Associated Liver Disease. This includes a liver biopsy to assess the stage of liver fibrosis.

    Additional tests may include blood tests and imaging studies to evaluate liver function and structure.

  3. Step 3

    Randomization

    Participants are randomly assigned to receive either the study medication Fazirsiran or a placebo, which is a substance with no active medication, administered as a subcutaneous injection.

  4. Step 4

    Treatment phase

    The treatment phase involves receiving the assigned injection every four weeks. The dosage and frequency are determined by the study protocol.

    Regular follow-up visits are scheduled to monitor health status, manage any side effects, and assess the effectiveness of the treatment.

  5. Step 5

    Mid-study assessment

    At approximately week 106, a liver biopsy is conducted to evaluate changes in liver fibrosis. This helps determine the effectiveness of the treatment.

    Additional assessments may include blood tests and imaging to monitor liver health.

  6. Step 6

    Continuation of treatment

    Participants continue to receive the assigned treatment and attend regular follow-up visits. Health status and treatment effects are continuously monitored.

  7. Step 7

    Final assessment

    At the end of the study, around week 202, a final liver biopsy is performed to assess the long-term effects of the treatment on liver fibrosis.

    Final evaluations include blood tests and imaging studies to provide a comprehensive overview of liver health.

  8. Step 8

    Study completion

    Upon completion of the study, participants receive a summary of their health status and any relevant findings from the trial.

    Participants may be offered the opportunity to continue receiving the study medication if it is found to be beneficial and safe.

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 type related to Alpha-1 Antitrypsin Deficiency. If this diagnosis is not already in their medical records, they will need to undergo testing to confirm it.
  • The participant can be of any sex and must be aged between 18 and 75 years old.
  • The participant must have evidence of METAVIR stage F2, F3, or F4 liver fibrosis. This is a way to measure liver scarring. It will be checked by a liver biopsy, which is a small sample of liver tissue taken for testing. This can be done during the screening period or confirmed by a previous biopsy done within 6 months before joining the study.
  • The participant must have a lung condition that meets specific criteria listed in the study protocol. This means their lung health will be evaluated to ensure it fits the study requirements.

Who cannot join the trial?

10 criteria

  • Patients with any other serious liver disease cannot participate.
  • Patients who have had a liver transplant are not eligible.
  • Patients with a history of alcohol or drug abuse in the past year cannot join the study.
  • Patients who are pregnant or breastfeeding are not allowed to participate.
  • Patients with any other medical condition that might interfere with the study cannot take part.
  • Patients who are currently participating in another clinical trial are not eligible.
  • Patients who have had a significant allergic reaction to the study medication or similar medications cannot participate.
  • Patients with uncontrolled high blood pressure are not eligible.
  • Patients with active infections that require treatment cannot join the study.
  • Patients with a history of cancer within the last five years, except for certain skin cancers, are not eligible.
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Investigated drugs

Fazirsiran is a medication being studied for its potential to help people with liver disease caused by a condition called Alpha-1 Antitrypsin Deficiency (AATD). This condition can lead to liver damage over time. Fazirsiran is designed to target and reduce the harmful effects of the abnormal protein that builds up in the liver due to AATD. By doing this, it aims to improve the health of the liver and reduce the amount of scarring, or fibrosis, in the liver tissue. The study is looking at how well Fazirsiran works in improving liver health and whether it is safe for patients to use.

What is already known about the treatment

Fazirsiran – Fazirsiran is administered as an injection and is currently being studied in clinical trials for its effectiveness and safety in treating liver disease associated with Alpha-1 Antitrypsin Deficiency. This medication is in the advanced stages of research, specifically a Phase 3 trial, which means it is being tested on a larger group of people to confirm its benefits and monitor side effects. The main therapeutic use of Fazirsiran is to improve liver fibrosis, which is a type of liver damage, in patients with this genetic condition. At the molecular level, Fazirsiran works by targeting and reducing the abnormal protein that accumulates in the liver due to this deficiency, helping to prevent further liver damage. It is classified as a therapeutic agent aimed at treating genetic liver diseases.

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 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 fibrosis, where scar tissue forms in the liver. As the disease progresses, fibrosis can advance to cirrhosis, a condition where the liver is severely scarred and its function is impaired. The progression of liver damage can vary, with some individuals experiencing more rapid advancement than others. The disease is often monitored through liver biopsies and imaging to assess the extent of fibrosis and liver stiffness.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2022-501943-34-00Protocol codeTAK-999-3001Estimated enrolment160 patientsSponsorTakeda Development Center Americas Inc.

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On this site, “treatment” means an investigational medicine being studied in a clinical trial. Its safety and efficacy for the use being studied have not yet been confirmed, some participants may receive a placebo or a comparator medicine, and taking part does not guarantee any health benefit. The decision to take part is made by the doctor at the research site. This site is for information only and does not replace medical advice.

This service is not affiliated with the European Commission, the EMA, or the official CTIS system. Most information comes from publicly available international clinical-trial registries, supplemented by data from academic sites, national regulators and commercial sponsors. On this site, “treatment” and “therapy” mean a medicine being tested in a clinical trial. Its safety and effectiveness in the use being studied are not yet confirmed, some participants may receive a placebo or a comparator, and taking part does not guarantee a health benefit. The doctor at the research site decides who can take part. This site provides information, not medical advice. Certain content and visual elements on this website have been generated or enhanced using artificial intelligence (AI).