Skip to content
Clinical Trials – home

Rare diseases

Investigational molecules

Locations

Our offerNewsroom

Recruiting

Study on Dopaminergic Pathway Disruption in Comatose Patients with Traumatic Brain Injury Using [18F]LBT-999

Verified siteInvestigationalNo 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 the effects of severe Traumatic Brain Injury (TBI) that leads to a coma. The study aims to understand how this type of injury affects the brain's dopaminergic pathways, which are involved in the production and regulation of dopamine, a chemical that plays a key role in brain function. The trial uses a special imaging agent called [18F]LBT-999, which is a solution for injection. This agent helps to visualize the brain's dopamine transporters during a type of brain scan known as a PET scan.

The purpose of the study is to explore the metabolic changes in the brain's dopamine network in patients who have experienced a traumatic coma. Participants will receive the [18F]LBT-999 injection, and then undergo a PET scan to observe how the agent binds to dopamine transporters in the brain. This will help researchers compare the brain activity of patients with traumatic coma to those without such injuries. The study will also look at how these changes relate to the patient's recovery and overall brain function over time.

Throughout the study, participants will be monitored at different intervals, including 3 months, 6 months, and 1 year after the initial brain injury. This will help assess their neurological recovery and quality of life. The study aims to provide valuable insights into the recovery process of patients with severe traumatic brain injuries and potentially improve future treatment approaches.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial assessment

    Upon joining the study, an initial assessment is conducted to confirm eligibility. This includes verifying age, social security affiliation, and obtaining informed consent. For patients, a trusted person may provide consent if necessary.

    Eligibility criteria include being between 18 and 65 years old, having experienced a non-penetrating traumatic brain injury (TBI) within the last 30 days, and showing clinical stability without the need for specific management that would prevent medical transfer.

  2. Step 2

    Discontinuation of sedatives

    Patients must have discontinued sedative treatments for more than 48 hours before participating in the trial. This ensures that the effects of sedatives do not interfere with the study results.

  3. Step 3

    Clinical stability check

    A check for clinical stability is performed to ensure there is no hemodynamic, respiratory, or metabolic failure that would contraindicate a medical transfer to the imaging center.

  4. Step 4

    Imaging procedures

    The study involves the use of a radiotracer called [18F]LBT-999, which is administered as a solution for injection through an intravenous route.

    Positron Emission Tomography (PET) scans are conducted to assess the binding of the radiotracer to dopamine transporters in the brain. This helps in characterizing metabolic abnormalities in the dopaminergic network.

  5. Step 5

    Follow-up assessments

    Neurological outcomes are assessed at 3 months, 6 months, and 1 year after the initial imaging procedures. This includes evaluations using the Coma Recovery Scale-Revised (CRS-R) and the Disability Rating Scale (DRS).

    Quality of life is also assessed using the Quality of Life after Brain Injury (QOLIBRI) scale.

Who can join the trial?

10 criteria

  • Participants must be female or male and between 18 and 65 years old.
  • Participants must be part of a social security scheme or be a beneficiary of such a scheme.
  • Informed consent must be signed by the participant or by a trusted person if the participant is unable to do so. Informed consent means agreeing to participate in the study after understanding all the details.
  • Participants must be patients who have been admitted to the hospital due to a non-penetrating traumatic brain injury (TBI) that happened less than 30 days ago. This means the injury did not break through the skull.
  • Participants must have experienced a traumatic coma upon hospital admission, which is a state of deep unconsciousness. This is measured by a Glasgow Coma Scale (GCS) score of less than 10, with a motor score (M) of less than 6. The GCS is a scale used to assess consciousness after a brain injury.
  • Sedative treatments must have been stopped for more than 48 hours. Sedatives are medications that make you calm or sleepy.
  • Participants must be clinically stable, meaning they do not have any heart, breathing, or metabolic problems that need special treatment and would prevent them from being safely moved to the imaging center.
  • For the TC-COMA group: Participants must have a severe TBI with a prolonged loss of consciousness (coma), defined by an initial GCS score of less than 8 and a motor score of less than 6, without regaining consciousness (GCS less than 10 with M less than 6) on the day of inclusion.
  • For the severe TC-ROS group: Participants must have a severe TBI with a prolonged loss of consciousness (coma), defined by an initial GCS score of less than 8 and a motor score of less than 6, but have shown signs of regaining consciousness, such as responding to simple commands (GCS 10 or more with M equal to 6).
  • For control subjects: Participants must be matched in age (plus or minus 2 years) and sex to patients in the TC-COMA group.

Who cannot join the trial?

3 criteria

  • Patients who are not in a coma due to a severe traumatic brain injury cannot participate. A coma is a state of deep unconsciousness where a person cannot be awakened.
  • Patients who are not within the specified age range for the study cannot participate. The age range is not specified here, but it is important for eligibility.
  • Patients who are part of a vulnerable population cannot participate. A vulnerable population includes groups who may have limited ability to give informed consent or are at higher risk of harm.
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.

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

[18F]LBT-999 is a special type of imaging agent used in this clinical trial. It helps doctors see how the brain is working by highlighting certain areas when scanned. In this study, it is used to look at the brain's dopamine system in patients who have had a severe brain injury and are in a coma. This imaging agent helps researchers understand how the brain's dopamine pathways are affected by the injury and how they might recover over time. By using this agent, doctors can get a clearer picture of the brain's activity and potentially find ways to help patients recover better from their injuries.

What is already known about the treatment

[18F]LBT-999 – This medication is administered as a radiotracer, which means it is given in a form that can be detected by imaging equipment to study brain activity. Currently, it is being researched in clinical trials to understand its effects and potential benefits in medicine, particularly for patients who have suffered a severe traumatic brain injury and are in a coma. The main use of [18F]LBT-999 is to help identify changes in the brain's dopamine system, which is important for understanding recovery processes in these patients. At the molecular level, it works by binding to specific sites in the brain associated with dopamine, allowing doctors to see how these areas are functioning. This medication falls under the category of diagnostic radiopharmaceuticals, which are used to help visualize and diagnose conditions in the body.

Investigated diseases

Traumatic Brain Injury – Traumatic Brain Injury (TBI) occurs when an external force injures the brain, often due to falls, vehicle accidents, or violence. The injury can lead to a range of physical and cognitive impairments, depending on the severity and location of the damage. In severe cases, TBI can result in a comatose state, where the patient is unconscious and unresponsive to external stimuli. The progression of TBI involves initial damage at the moment of impact, followed by secondary processes such as inflammation and swelling that can exacerbate the injury. Over time, patients may experience changes in brain function, including difficulties with movement, memory, and emotional regulation. Recovery varies widely, with some individuals regaining significant function while others may have lasting impairments.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IVTrial ID2023-504893-39-00Protocol codeC22-62Estimated enrolment55 patientsSponsorInstitut National De La Sante Et De La Recherche Medicale

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.