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Study on Long-Term Safety and Effectiveness of Vanzacaftor, Tezacaftor, and Deutivacaftor for Cystic Fibrosis in Patients Aged 1 Year and Older

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 Cystic Fibrosis, a genetic condition that affects the lungs and digestive system. The treatment being tested is a combination of three medications: Vanzacaftor, Tezacaftor, and Deutivacaftor, which are taken as a film-coated tablet. These medications are designed to work together to help improve the function of certain proteins in the body that are affected by cystic fibrosis.

The purpose of this study is to evaluate the long-term safety and effectiveness of this triple combination therapy in individuals with cystic fibrosis who are 1 year of age and older. Participants in the study will take the medication orally, meaning they will swallow the tablets, over a period of time. The study will monitor how well the treatment is tolerated by the participants and will look for any side effects or changes in health indicators such as weight, height, and lung function.

Throughout the study, researchers will collect information on various health measures, including changes in lung function and the number of hospital visits related to cystic fibrosis. The study aims to provide valuable insights into how this combination therapy can help manage cystic fibrosis over the long term, ensuring that it is safe and beneficial for those who take it.

The research process

The trial runs in 4 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 or your legally appointed representative will sign and date an informed consent form (ICF). If applicable, you will also sign an assent form, which is a document that shows your agreement to participate.

    It is important that your legal representative or guardian understands the study requirements and ensures that you can follow the instructions and complete the study as planned.

  2. Step 2

    Treatment period

    During the treatment period, you will take a medication called VX-121/VX-661/VX-561, which comes in the form of a film-coated tablet. This medication is taken orally, meaning you will swallow it.

    The medication is a combination of three active substances: vanzacaftor, tezacaftor, and deutivacaftor. The exact dosage and frequency will be provided by the study team, and it is important to follow their instructions carefully.

    You will continue your regular cystic fibrosis treatment regimen while participating in the study.

  3. Step 3

    Monitoring and assessments

    Throughout the study, your health will be monitored to evaluate the long-term safety and tolerability of the medication. This includes checking for any side effects, conducting laboratory tests, and measuring vital signs such as heart rate and blood pressure.

    Additional assessments will include measuring changes in your sweat chloride levels, lung function, and other health indicators related to cystic fibrosis.

  4. Step 4

    Completion of the study

    The study is expected to continue until October 31, 2025. Upon completion, you will have a final assessment to evaluate your overall health and the effects of the medication.

    Your participation in the study will contribute to understanding the long-term safety and effectiveness of the medication for individuals with cystic fibrosis.

Who can join the trial?

8 criteria

  • The patient or the patient's legally appointed representative must sign and date an informed consent form (ICF). The patient will also sign an assent form, which is a document showing they agree to participate.
  • The patient's legal representative or guardian must understand the study requirements and be able to ensure the patient follows the study plan.
  • The patient must not have withdrawn consent from the previous related study.
  • The patient must meet at least one of the following conditions:
    • Completed the study drug treatment in the previous study.
    • Had interruptions in the study drug treatment in the previous study but did not stop the study drug early and completed all required visits up to the last scheduled visit of the treatment period in the previous study.
    • The patient must be willing to continue their current **Cystic Fibrosis** (CF) treatment plan throughout the study.
    • The study is open to both **male** and **female** patients.
    • The study includes patients who are considered a **vulnerable population**, meaning they may need special protection or care.

Who cannot join the trial?

10 criteria

  • Patients who do not have Cystic Fibrosis cannot participate.
  • Patients who are not within the specified age range cannot participate.
  • Patients who are not willing to follow the study procedures cannot participate.
  • Patients who have other medical conditions that might interfere with the study cannot participate.
  • Patients who are pregnant or breastfeeding cannot participate.
  • Patients who are currently participating in another clinical trial cannot participate.
  • Patients who have a history of non-compliance with medical treatments cannot participate.
  • Patients who have allergies to the study medication cannot participate.
  • Patients who have had recent surgery or are planning to have surgery during the study cannot participate.
  • Patients who have a history of drug or alcohol abuse cannot participate.
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Investigated drugs

  • Vanzacaftor

    is a medication used in this clinical trial to help improve the function of a protein that is defective in people with cystic fibrosis. This protein is important for maintaining the balance of salt and water in the lungs and other organs. By improving the function of this protein, Vanzacaftor aims to help reduce the symptoms of cystic fibrosis and improve lung function.

  • Tezacaftor

    is another medication in the trial that works alongside Vanzacaftor. It also helps to improve the function of the defective protein in cystic fibrosis patients. Tezacaftor is designed to help the protein reach the right place in the cell where it can work properly, which may help improve breathing and reduce the frequency of lung infections.

  • Deutivacaftor

    is the third medication in the combination therapy being tested in this trial. Like the other two medications, it helps to enhance the function of the protein that is not working correctly in people with cystic fibrosis. Deutivacaftor is intended to further support the other medications in improving lung function and overall health in patients with this condition.

What is already known about the treatment

Vanzacaftor/Tezacaftor/Deutivacaftor – This medication is administered orally in the form of tablets and is currently being studied in clinical trials for its long-term safety and effectiveness in treating cystic fibrosis, a genetic disorder affecting the lungs and digestive system. The medication is a combination therapy designed to help improve the function of a protein that is defective in people with cystic fibrosis. By enhancing the activity of this protein, the medication aims to reduce the symptoms and complications associated with the disease. It falls under the pharmacological classification of CFTR modulators, which are drugs that target the cystic fibrosis transmembrane conductance regulator protein.

Investigated diseases

Cystic Fibrosis – Cystic Fibrosis is a genetic disorder that affects the respiratory and digestive systems. It is characterized by the production of thick and sticky mucus that can clog the airways and lead to breathing difficulties. Over time, this mucus buildup can cause persistent lung infections and damage to the lungs. In the digestive system, the thick mucus can block the ducts of the pancreas, preventing digestive enzymes from reaching the intestines and leading to malnutrition. The disease often results in chronic coughing, wheezing, and frequent lung infections. As it progresses, individuals may experience reduced lung function and difficulty in maintaining a healthy weight.
Trial detailsLast updated 7 Oct 2026
Age0-17PhasePhase IIITrial ID2022-503081-74-00Protocol codeVX22-121-106Estimated enrolment138 patientsSponsorVertex Pharmaceuticals Inc.

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