Skip to content
Clinical Trials – home

Rare diseases

Investigational molecules

Locations

Our offerNewsroom

Not recruitingRare disease

Study on VX-522 and Ivacaftor for Adults with Cystic Fibrosis Unresponsive to CFTR Modulator Therapy

Fast replyRegistered drugNo placebo
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

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 study will test a new treatment called VX-522, which is delivered as a mist through a device called the eFlow Nebuliser System. This treatment is being tested alone and in combination with another medication called Ivacaftor, which is taken as a tablet. The purpose of the study is to evaluate the safety and tolerability of these treatments in adults with Cystic Fibrosis who have a specific genetic makeup that does not respond to existing therapies.

Participants in the study will receive either the VX-522 treatment alone or in combination with Ivacaftor. The study will involve different groups receiving varying doses to determine the most effective and safe dosage. The study will monitor participants' health and any side effects they may experience during the treatment period. The eFlow Nebuliser System is specifically designed to deliver the VX-522 treatment effectively to the lungs.

The study will take place over several weeks, with participants attending regular check-ups to assess their health and the effects of the treatment. The goal is to gather information on how well the treatment works and how safe it is for people with Cystic Fibrosis. This research could lead to new treatment options for those who have not benefited from current therapies.

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, the participant will sign an informed consent form, indicating understanding and agreement to participate.

    Eligibility criteria include being between 18 and 65 years old, having a body mass index (BMI) of less than 30, and a total body weight of more than 50 kg.

    Participants must have cystic fibrosis with specific genetic mutations not responsive to current therapies and must be nonsmokers or ex-smokers for at least three months.

  2. Step 2

    Initial assessment

    An initial assessment will be conducted to ensure stable cystic fibrosis disease and a forced expiratory volume (FEV1) of at least 40% of the predicted value for age, sex, and height.

    Participants must be on a stable cystic fibrosis treatment regimen for 28 days prior to dosing and agree to maintain this regimen throughout the study.

  3. Step 3

    Single ascending dose (SAD) phase

    Participants will receive a single dose of VX-522 via inhalation to evaluate safety and tolerability.

    Monitoring will include assessments of adverse events, laboratory tests, ECGs, vital signs, and immune response.

  4. Step 4

    Multiple ascending dose (MAD) phase - treatment arm 1

    Participants in Treatment Arm 1 will receive multiple doses of VX-522 via inhalation.

    The focus will be on evaluating safety, tolerability, and changes in lung function over time.

  5. Step 5

    Multiple ascending dose (MAD) phase - treatment arm 2

    Participants in Treatment Arm 2 will receive multiple doses of VX-522 via inhalation, co-administered with ivacaftor (Kalydeco 150 mg tablets) taken orally.

    The aim is to assess safety, tolerability, and changes in lung function, comparing results to baseline measurements.

  6. Step 6

    End of study assessments

    Final assessments will be conducted to evaluate the overall safety and effectiveness of the treatments.

    Participants will undergo various tests, including spirometry to measure lung function, and other clinical evaluations.

Who can join the trial?

9 criteria

  • The patient must sign and date a form that shows they agree to participate in the study.
  • The patient should be willing and able to attend scheduled visits, follow the treatment plan, adhere to study rules, undergo lab tests, follow guidelines for preventing pregnancy, and participate in other study procedures.
  • The patient must be between 18 and 65 years old.
  • The patient should have a body mass index (BMI) of less than 30.0 kg/m² and weigh more than 50 kg. BMI is a measure that uses height and weight to estimate body fat.
  • The patient must be a nonsmoker or have quit smoking at least 3 months before the study starts. This will be confirmed with a urine or blood test.
  • The patient must have specific genetic changes called **CFTR mutations** on both copies of a gene that do not respond to certain treatments known as **CFTR modulator therapy**.
  • The patient should have stable **Cystic Fibrosis (CF)**, as determined by the study doctor, and a lung function test result (**FEV1**) that is at least 40% of what is expected for their age, sex, and height. FEV1 is a test that measures how much air you can forcefully exhale in one second.
  • The patient must be on a stable CF treatment plan for at least 28 days before starting the study and be willing to continue this treatment plan (except for the study drug) until the study ends.
  • For those participating in a specific part of the study involving a procedure called **bronchoscopy**, the patient must have a normal platelet count and a normal result on a blood test called **prothrombin time test international normalized ratio (INR)**, which checks how well the blood clots.

Who cannot join the trial?

10 criteria

  • Patients who do not have Cystic Fibrosis cannot participate. Cystic Fibrosis is a genetic condition that affects the lungs and digestive system.
  • Patients who are not within the specified age range for the study cannot participate. The age range is typically defined by the study organizers.
  • Patients who are not able to follow the study procedures or take the study medication as required cannot participate.
  • Patients who have other medical conditions that might interfere with the study or make participation unsafe cannot participate.
  • Patients who are pregnant or breastfeeding cannot participate, as the study may involve risks to the baby.
  • Patients who are currently participating in another clinical trial cannot participate, as this could affect the results of the study.
  • Patients who have a history of allergic reactions to the study medication or similar medications cannot participate.
  • Patients who have used certain medications or treatments recently that could interfere with the study cannot participate.
  • Patients who have a history of drug or alcohol abuse that might affect their ability to follow the study procedures cannot participate.
  • Patients who have had a recent surgery or are planning to have surgery during the study period cannot participate.
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.

We usually reply within a few days

Verified sites

All sites with verified contact details – recruitment status may not be available; ask directly

Trial locations

Where you can join this trial

Countries are shaded by recruitment status. Click a recruiting country to ask about joining there.

Not recruiting
Not finding your country?

Not sure what to do next?

Joining a clinical trial can seem overwhelming. We guide you step by step, so you know exactly what to expect and how we support you through the process.

See the full process and FAQ

Investigated drugs

  • VX-522

    is an investigational medication being studied for its potential to treat cystic fibrosis in patients whose genetic type does not respond to existing CFTR modulator therapies. The study aims to assess the safety and tolerability of this medication when given in increasing doses.

  • Ivacaftor

    is a medication used in combination with VX-522 in one of the treatment arms of the study. It is designed to help improve the function of the CFTR protein in patients with cystic fibrosis, potentially enhancing the effectiveness of VX-522.

What is already known about the treatment

VX-522 – This medication is administered as an inhalation treatment, designed for individuals with cystic fibrosis who have a specific genetic makeup that does not respond to existing CFTR modulator therapies. Currently, VX-522 is in the early stages of clinical trials, specifically Phase 1/2, to assess its safety and effectiveness. It is primarily indicated for cystic fibrosis, a condition that affects the lungs and digestive system. VX-522 works by targeting the defective CFTR protein at the molecular level, aiming to restore its function and improve symptoms. It falls under the pharmacological classification of gene therapy agents.

Investigated diseases

Cystic Fibrosis – Cystic Fibrosis is a genetic disorder that affects the respiratory and digestive systems. It is caused by mutations in the CFTR gene, leading to the production of thick and sticky mucus. This mucus can clog the airways, causing breathing difficulties and frequent lung infections. Over time, the buildup of mucus can also affect the pancreas, hindering the digestion and absorption of nutrients. The disease progresses with persistent coughing, wheezing, and decreased lung function. It is a lifelong condition that requires ongoing management to alleviate symptoms and improve quality of life.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase I/IITrial ID2023-504786-23-00Protocol codeVX21-522-001Estimated enrolment36 patientsSponsorVertex Pharmaceuticals Inc.

sourced from the EU Clinical Trials Register and site verification

Want to learn more about this trial or check if you can participate?

Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.