AzTrials
AzTrials

Congenital Diaphragmatic HerniaSmart-FETONCT04931212

Fetoscopic Endoluminal Tracheal Occlusion (FETO) With Smart-TO

A study testing FETO with Smart-TO balloon in people with Congenital Diaphragmatic Hernia, run by Assistance Publique - Hôpitaux de Paris at 2 sites in France.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
Search all trials

Trial summary

The purpose of this study is to make the proof of concept and to evaluate the safety of fetoscopic endoluminal tracheal occlusion (FETO) using Smart-TO device in fetuses with congenital diaphragmatic hernia and moderate to severe pulmonary hypoplasia Read more about this study

Who is it for?
Ages 18 years and older, women only
Conditions the study is for
Congenital Diaphragmatic Hernia
What is being tested?
FETO with Smart-TO balloon
Type of treatment
Surgery or procedure
Could I receive a placebo?
No, everyone receives an active treatment
How many people
23 participants
Where
2 sitesFrance
Study dates
4 Aug 2021to 5 Sep 2024
Phase
Interventional
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 years and older
  • Women only
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • Patients aged 18 years or more, who are able to consent, and affiliated to social security
  • Singleton pregnancy with fetus with isolated left-sided congenital diaphragmatic hernia (no additional malformation nor chromosomal abnormality) and:
  • Severe pulmonary hypoplasia defined as observed on expected 'lung-to-head ration' (O/E LHR) <25% irrespective of the liver position as measured between 27wks and 29wks + 6 days Or Moderate pulmonary hypoplasia defined as O/E LHR 25-34.9% (liver up or down) or O/E LHR 35-44.9% with liver up as measured between 30wks and 31wks + 6 days

Who cannot join

  • Maternal contraindication to fetoscopic surgery
  • Preterm premature rupture of the membranes (PPROM) or condition strongly predisposing to PPROM or premature delivery
  • Impossibility of remain close to the FETO center during the fetal occlusion period

Trial locations and contacts

2 sites in 1 country.

France2 sites

  • Hôpital Béclère

    Clamart, 92140

  • Hôpital Bicêtre

    Le Kremlin-Bicêtre, 94270

Other trials in France

About this study

Official title: Fetoscopic Endoluminal Tracheal Occlusion (FETO) With Smart-TO Device in Fetuses With Congenital Diaphragmatic Hernia and Moderate to Severe Pulmonary Hypoplasia: Proof of Concept and Safety Evaluation.

The purpose of this study is to make the proof of concept and to evaluate the safety of fetoscopic endoluminal tracheal occlusion (FETO) using Smart-TO device in fetuses with congenital diaphragmatic hernia and moderate to severe pulmonary hypoplasia

Read the detailed description

Congenital diaphragmatic hernia (CDH) leads to lung hypoplasia and impaired lung vasculature. Fetal lung growth may be stimulated by fetal endoscopic tracheal occlusion (FETO). In severe CDH, FETO may improve survival. In the moderate cases, the prematurity induced by the plug-unplug strategy limits the benefit from the lung growth induced by tracheal occlusion.

One of the main drawbacks of FETO is the need for in-utero reversal of tracheal occlusion by the balloon, as the current procedure involves re-establishment of patent airways either electively at 34 weeks' gestation or earlier if required, ideally at least 24 h before birth. Unfortunately, removal of the balloon is a difficult, invasive, and risky procedure. Furthermore, it requires a specialist team to be able to reverse the occlusion at all times. As a result, it is recommended that the patient stays close to a FETO center during the whole duration of the occlusion, which may limit the acceptability of FETO.

The Smart-TO balloon allows an easy, remotely controlled, and non-invasive reversal occlusion, so it allows to overcome issues related to the airway reestablishment. The technology solution is based on a magnetic valve that opens under the influence of the peripheral magnetic field around a magnetic resonance (MR) scanner. The opening of the valve induces the deflation of the balloon, which is then washed out by the fluid coming out from the lungs.

The purpose of this study is to make the proof of concept and to evaluate the safety of fetoscopic endoluminal tracheal occlusion (FETO) using Smart-TO device in fetuses with congenital diaphragmatic hernia and moderate to severe pulmonary hypoplasia. Secondary objectives include evaluation of prematurity, preterm premature rupture of membranes, lung growth, and survival at discharge in case of FETO with Smart-TO balloon.

FETO with Smart-TO balloon will be performed between 27 and 31wks + 6 days depending on the severity of pulmonary hypoplasia, according to the same technique that is used with the balloon usually used for FETO procedure. The unplug procedure will be performed between 34 and 34wks + 6 days or earlier if required. The patient will be asked to make a peripheral course around the MR scanner in order to open the magnetic valve and induce the deflation of the balloon. Ultrasound scan will be performed before and after the unplug procedure, in order to check the balloon did not deflate spontaneously at the time of the unplug, and to check the balloon deflates thanks to the magnetic fringe field of the MR scan. Expelling of the Smart-TO balloon outside the airways will be check at birth by a thorax X-ray.

Patients will be monitored during the whole duration of the study so serious unexpected or adverse reactions can be recorded.

Being tested
FETO with Smart-TO balloon
Keywords
Congenital diaphragmatic hernia, Fetal endoscopic tracheal occlusion, Smart-TO balloon, Proof of concept, Safety study
Medical subject headings
Hernias, Diaphragmatic, Congenital

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • FETO with Smart-TO balloonProcedure or surgery

    Also called Unplug

    Fetal endoscopic tracheal occlusion using the Smart-TO balloon Unplug procedure by peripheral course around the MR scanner

Study groups in NCT04931212
Study groupRoleWhat they receive
InterventionExperimentalNot described
Receives: Procedure: FETO with Smart-TO balloon

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Deflation of the Smart-TO balloon after exposure to the fringe field of the MRI

    No visualization of the balloon at ultrasound scan

    Measured: Between 34 and 34+6 amenorrhea weeks

  2. Expelling of the Smart-TO balloon outside the airways

    Thorax X-ray of the neonate

    Measured: At birth

Secondary outcomes (8)

  1. Serious unexpected or adverse reactions

    Adverse reactions monitoring during the whole study duration

    Measured: From date of inclusion until discharge date from hospitalization of newborn, up 15 months

  2. Spontaneous deflation of the balloon

    Ultrasound scan

    Measured: Between the FETO (27amenorrhea weeks) and the unplug procedure (34 amenorrhea weeks)

  3. Prematurity

    Gestational age at birth

    Measured: At birth

  4. Preterm premature rupture of the membranes (PPROM)

    Event of PPROM and gestational age at PPROM

    Measured: from date of inclusion until delivery, up to 37 amenorrhea weeks

  5. Fetal lung growth

    O/E LHR measurement

    Measured: Before the unplug procedure

  6. Survival at discharge

    Neonate survival

    Measured: From date of inclusion until discharge date from hospitalization of newborn, up to 6 months

  7. Survival at 6 months of age

    Neonate survival

    Measured: 6 months after birth

  8. Oxygen dependence

    Measured: 6 months after birth

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted18 Jun 2021
  2. Study start4 Aug 2021
  3. Primary completion14 Jan 2024
  4. Study completion5 Sep 2024

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Treatment
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrolment
23 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT04931212
Sponsor's protocol ID
2020-A02834-35
Other IDs
2020-A02834-35
Acronym
Smart-FETO
Status last verified
Oct 2025
First submitted
6 Feb 2021
Last updated
20 Nov 2025
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
No

Publications

  • Russo FM, Sananes N, Letourneau A, Devlieger R, Megier C, Lewi L, Huyn VTN, Aertsen M, Dumery G, Deprest J, Benachi A; SMART-TO consortium. Non-invasive removal of the Smart tracheal occlusion device for fetal congenital diaphragmatic hernia: a single-arm, open-label, phase 1 study. Lancet. 2026 Jul 11;408(10550):153-161. doi: 10.1016/S0140-6736(26)00664-1. Epub 2026 Jun 23.

    PubMed 42335922

Questions about this trial

What is this clinical trial studying?

A study testing FETO with Smart-TO balloon in people with Congenital Diaphragmatic Hernia, run by Assistance Publique - Hôpitaux de Paris at 2 sites in France.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 3 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 20 Nov 2025. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 2 sites in France. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Deflation of the Smart-TO balloon after exposure to the fringe field of the MRI (time frame: Between 34 and 34+6 amenorrhea weeks). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT04931212, which also lists 1 linked publication.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 20 Nov 2025.

AzTrials uses cookies for analytics and advertising. You can accept or reject them; the site works either way. Privacy Policy.

Free account

Log in to keep searching

You’ve used your 3 free searches. AzTrials is free: log in or create a free account to keep searching clinical trials and save the ones you want to follow.

Create a free accountLog in