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Long-Term Safety Study of BI 3720931 for Patients with Cystic Fibrosis from a Previous Trial

Verified siteInvestigationalNo 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 focuses on monitoring the long-term health of individuals with cystic fibrosis who previously participated in a study involving a treatment called BI 3720931. Cystic fibrosis is a genetic condition that affects the lungs and digestive system, leading to severe respiratory and digestive problems. The treatment being studied, BI 3720931, is an inhaled gene therapy designed to help manage the symptoms of cystic fibrosis. The purpose of this study is to evaluate the long-term safety and effectiveness of this treatment.

Participants in this study have already received at least one dose of BI 3720931 or a matching placebo in a previous trial. The study will follow these participants over an extended period to observe any potential long-term effects of the treatment. This includes monitoring for any new health issues such as serious infections, neurological disorders, or autoimmune conditions. The study will also track the time it takes for any loss of treatment effectiveness, particularly in lung function, which is measured by a test called forced expiratory volume in 1 second (FEV1).

The study is designed to last up to 15 years, allowing researchers to gather comprehensive data on the long-term impact of BI 3720931. Throughout this period, the occurrence of any serious adverse events will be recorded, providing valuable insights into the safety profile of the treatment. This information will help determine the potential benefits and risks of using BI 3720931 as a long-term treatment option for people with cystic fibrosis.

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

    Enrollment

    Participation begins after signing a written informed consent. This consent is in line with international guidelines and local laws.

    Eligibility requires previous participation in a study with BI 3720931 and having received at least one dose of the medication or a placebo.

  2. Step 2

    Initial assessment

    An initial health assessment is conducted to establish a baseline for monitoring purposes.

    This assessment includes measuring lung function, specifically the forced expiratory volume in 1 second (FEV1).

  3. Step 3

    Medication administration

    The study involves monitoring after a single dose of BI 3720931, which is an inhaled gene therapy.

    The medication is administered as a nebuliser solution through inhalation.

  4. Step 4

    Long-term monitoring

    Participants are monitored for up to 15 years to assess long-term safety and health status.

    Monitoring includes checking for any new serious health issues such as malignancies, neurological disorders, or infections potentially related to the product.

  5. Step 5

    Regular health evaluations

    Regular evaluations are conducted to track lung function and overall health.

    The time to any loss of efficacy, such as a significant drop in lung function, is recorded.

  6. Step 6

    Adverse event tracking

    Any adverse events, including serious ones, are documented throughout the study period.

    The presence of replication-competent lentivirus is also monitored.

Who can join the trial?

5 criteria

  • The study is for people with cystic fibrosis, a genetic condition that affects the lungs and digestive system.
  • Participants must have been part of a previous study with the medication BI 3720931 and received at least one dose of it or a placebo, which is a harmless pill that looks like the real medication but has no effect.
  • Participants need to provide a signed and dated written consent form, which is a document that shows they agree to join the study. This must be done according to international and local rules for clinical trials.
  • The study is open to both males and females.
  • Participants can be children or adults, as the study includes a range of ages.

Who cannot join the trial?

7 criteria

  • Participants with any other serious health condition that could affect their safety during the trial.
  • Individuals who have had a recent infection that could interfere with the trial.
  • People who are currently taking medications that might interact with the trial treatment.
  • Participants who have a history of allergic reactions to similar treatments.
  • Individuals who are pregnant or breastfeeding.
  • People who have participated in another clinical trial recently.
  • Participants who are unable to follow the trial procedures or instructions.
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Investigated drugs

BI 3720931 is an inhaled gene therapy that uses a lentiviral vector. It is designed to help people with cystic fibrosis by delivering genetic material directly to the lungs. This therapy aims to provide long-term benefits by potentially correcting the underlying genetic defect associated with cystic fibrosis. The clinical trial is focused on evaluating the long-term safety and effectiveness of this therapy after a single dose has been administered in a previous study.

What is already known about the treatment

BI 3720931 – This medication is administered as an inhaled treatment and is currently being evaluated in clinical trials for its long-term safety and effectiveness in individuals with cystic fibrosis. It is a gene therapy using a lentiviral vector, designed to deliver genetic material directly to the lungs to address the underlying cause of cystic fibrosis. The medication works by introducing a functional copy of the gene that is defective in cystic fibrosis patients, aiming to restore normal function at the cellular level. BI 3720931 is classified as a gene therapy product, representing a novel approach in the treatment of genetic disorders.

Investigated diseases

Cystic fibrosis – Cystic fibrosis is a genetic disorder that primarily affects the lungs and digestive system. It is caused by mutations in the CFTR gene, leading to the production of thick and sticky mucus. This mucus can clog the airways, leading to breathing difficulties and frequent lung infections. Over time, the buildup of mucus can cause damage to the lungs and other organs. The disease also affects the pancreas, hindering the release of digestive enzymes necessary for proper food digestion. As a result, individuals with cystic fibrosis may experience malnutrition and poor growth.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase ITrial ID2023-504909-37-00Protocol code1504-0003Estimated enrolment27 patientsSponsorBoehringer Ingelheim Espana S.A.

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