Glanzmann ThrombastheniaGLATNCT06234813
Targeting TFPI With Concizumab to Improve Haemostasis in Glanzmann Thrombasthenia Patients: an in Vitro Study
A study testing Clot formation in whole blood under flow in a microfluidic flow chamber coated with tissue factor and collagen, : PRP viscoelastic changes under clot formation measured by thromboelastometry using RoTEM and Thrombin Generation Assay (TGA) in PRP using TF trigger in people with Glanzmann Thrombasthenia, run by University Hospital, Bordeaux at 1 site in France.
Trial summary
Glanzmann thrombasthenia is a rare genetic disorder caused by the absence or the dysfunction of the main receptor present on the surface of platelets, integrin αIIbβ3 or GPIIb-IIIa. The lack of this protein on the surface of platelets no longer allows these blood cells to bind to each other. Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Glanzmann Thrombasthenia
- What is being tested?
- Clot formation in whole blood under flow in a microfluidic flow chamber coated with tissue factor and collagen, : PRP viscoelastic changes under clot formation measured by thromboelastometry using RoTEM and Thrombin Generation Assay (TGA) in PRP using TF trigger
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 20 participants
- Where
- 1 siteFrance
- Study dates
- 6 Apr 2023to 17 Jul 2023
- 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
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Glanzmann Thrombasthenia Group:
- Patient ≥18 years old
- Patient with a clear diagnosis of Glanzmann Thrombasthenia (GT), whatever the subtype of disease
- Affiliated person or beneficiary of a social security scheme.
- Free, informed and written consent signed by the participant, and the investigator (at the latest on the day of inclusion and before any examination required by the research)
- Control Group:
Show all 11Show fewer
- Healthy donor ≥ 18 years old
- Healthy donor, without haemorrhagic ant thrombotic medical history
- Person should not work in the investigator's department.
- Affiliated person or beneficiary of a social security scheme
- Free, informed and written consent signed by the participant, and the investigator (at the latest on the day of inclusion and before any examination required by the research)
Who cannot join
- For both patient groups:
- Patient who has taken aspirin or a nonsteroidal anti-inflammatory medication within the previous 10 days
- Patient who has received a platelet transfusion or recombinant activated factor VII hemostatic treatment within the previous 7 days
- Patient who participated in another interventional study involving a drug within 30 days of entering this protocol
- Psychiatric, social or behavioral condition judged to be non-compatible with the respect of the protocol
- Adult protected by the law
Trial locations and contacts
1 site in 1 country.
About this study
Glanzmann thrombasthenia is a rare genetic disorder caused by the absence or the dysfunction of the main receptor present on the surface of platelets, integrin αIIbβ3 or GPIIb-IIIa.
The lack of this protein on the surface of platelets no longer allows these blood cells to bind to each other. This binding corresponds to the process of platelet aggregation.
Read more
Generally, local measures will control nasal and superficial bleeding whereas platelet transfusions are used to control or prevent life-threatening.
The main complication of this treatment is the risk of developing anti-αIIbβ3 antibodies directed against the absent protein and platelet transfusion therapy can become ineffective.
Activated recombinant factor VII (rFVIIa) provides an alternative treatment for GT patients who develop such antibodies. However, this therapy has a short duration of efficacy, requiring repeated intravenous administrations every 2 to 3 hours.
There is a new treatment, Concizumab, which has not yet been marketed. This treatment acts on TFPI (tissue factor pathway inhibitor). TFPI is a protein that occurs naturally in the body and prevents blood cells from binding to each other.
Concizumab works by blocking TFPI, which may allow sufficient clotting to prevent bleeding.
This treatment could replace recombinant activated factor VII (rFVIIa) because it has the advantage of a much longer duration of efficacy (about 3 days) and is administered subcutaneously.
Read the detailed description
This is in vitro research. The treatment will be tested on blood samples. This will allow us to evaluate in vitro the ability of Concizumab to restore coagulation compared to the usual treatments of platelet transfusions and recombinant activated factor VII (rFVIIa).
This is a single-center study conducted at the Bordeaux University Hospital, which included 10 with Glanzmann thrombasthenia patients and 10 healthy donors over a period of 12 months.
- Conditions
- Glanzmann Thrombasthenia
- Being tested
- Clot formation in whole blood under flow in a microfluidic flow chamber coated with tissue factor and collagen, : PRP viscoelastic changes under clot formation measured by thromboelastometry using RoTEM, Thrombin Generation Assay (TGA) in PRP using TF trigger, Global fibrinolytic capacity in PRP using reagents for in vitro triggering of the clot and its lysis, Concizumab
- Keywords
- Concizumab, Hemostatic capacity, Glanzmann Thrombasthenia
- Medical subject headings
- Thrombasthenia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Clot formation in whole blood under flow in a microfluidic flow chamber coated with tissue factor and collagenOther
TTAS (single measurements)
Clot formation in whole blood under flow (2000 s-1) in a microfluidic flow chamber coated with tissue factor and collagen (T-TAS with AR chip)
- 500 µL of whole blood for each point;
- 7 points for each condition;
- Around 4 mL of whole blood will be needed for each patient or healthy subject;
- Values for Area Under the Curve (Aritrary Unit), Occlusion Starting Time (min), Occlusion Time (min.) will be reported.
: PRP viscoelastic changes under clot formation measured by thromboelastometry using RoTEMOther
ROTEM (single measurements)
- ROTEM cups will be added
- 20 µL calcium reagent (STARTEM)
- 20 µL of 2,940-fold prediluted r-ExTEM reagent (50,000 fold dilution relative to 340 µL in the cup) added
- 300 µL spiked PRP at 250 G/L (2.5 mL of PRP/patient)
- Values for clot time (CT sec, clot formation time (CFT) sec, maximum clot formation (mm) will be reported.
Thrombin Generation Assay (TGA) in PRP using TF triggerOther
TGA (single measurements)
- The following will be added to well:
- 20 uL of PRP-Reagent
- 80 uL of spiked PRP (600 µL/patient at 100 G/L)
- 20 uL FluCa
- Values for thrombin activity versus time and the derived parameters incl. lag-time (min), time to peak (min), time to peak (min), ETP (Arbitrary Unit) will be reported.
Global fibrinolytic capacity in PRP using reagents for in vitro triggering of the clot and its lysisOther
Global fibrinolytic capacity (Lysis Timer) in 100 µL of PRP (250 G/L) using reagents for in vitro triggering of the clot (thrombin and calcium) and its lysis (tissue-plasminogenactivator (t-PA). Around 1 mL of PRP in total Lysis time in min
ConcizumabOther
Thrombin generation assay (TGA), microchip flow-chamber assay (T-TAS, rotational thromboelastometry and global fibrinolytic capacity to investigate and compare the effects of mixing concizumab (200, 1000 and 4000 ng/mL) with the main bleed treatment options for persons with GT
| Study group | Role | What they receive |
|---|---|---|
| Glanzmann Thrombasthenia Group | Experimental | Patient with a clear diagnosis of Glanzmann Thrombasthenia, whatever the subtype of disease Receives: Other: Clot formation in whole blood under flow in a microfluidic flow chamber coated with tissue factor and collagen; Other: : PRP viscoelastic changes under clot formation measured by thromboelastometry using RoTEM; Other: Thrombin Generation Assay (TGA) in PRP using TF trigger; Other: Global fibrinolytic capacity in PRP using reagents for in vitro triggering of the clot and its lysis; Other: Concizumab |
| Healthy donors | Active comparator | Healthy donor without haemorrhagic ant thrombotic medical history Receives: Other: Clot formation in whole blood under flow in a microfluidic flow chamber coated with tissue factor and collagen; Other: : PRP viscoelastic changes under clot formation measured by thromboelastometry using RoTEM; Other: Thrombin Generation Assay (TGA) in PRP using TF trigger; Other: Global fibrinolytic capacity in PRP using reagents for in vitro triggering of the clot and its lysis |
What is being measured
The primary outcome is the main question the study is designed to answer.
Effects of mixing concizumab compared with the main bleed treatment options for persons with GT
The samples will be analysed by measurement of in vitro hemostatic capacity :
- Clot formation in whole blood under flow (2000 s-1) in a microfluidic flow chamber coated with tissue factor and collagen. Values for Area Under the Curve (Aritrary Unit), Occlusion Starting Time (min), Occlusion Time (min.) will be reported
- PRP viscoelastic changes under clot formation measured by thromboelastometry. Values for clot time (sec), clot formation time (sec), maximum clot formation (mm) will be reported
- Thrombin Generation Assay in PRP using tissue factor trigger. Values for thrombin activity versus time and the derived parameters incl. lag-time (min.), time to peak (min), time to peak (min), ETP (Arbitrary Unit) will be reported
- Global fibrinolytic capacity (Lysis Timer in min) in whole blood using reagents for in vitro triggering of the clot and its lysis
Measured: One point at the inclusion
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted31 Jan 2024
- Study start6 Apr 2023
- Primary completion17 Jul 2023
- Study completion17 Jul 2023
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Glanzmann ThrombastheniaStudies of the same condition, open and under way.
- More trials run by University Hospital, BordeauxThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
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
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 20 participants (actual)
Sponsor and investigators
- Lead sponsor
- University Hospital, Bordeaux
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Mathieu FIORE, Principal investigator, University Hospital, Bordeaux
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06234813
- Sponsor's protocol ID
- CHUBX 2021/44
- Other IDs
- 2021-A02780-41
- Acronym
- GLAT
- Status last verified
- Sep 2023
- First submitted
- 21 Mar 2023
- Last updated
- 26 May 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Dubut J, Goin V, Derray C, Huguenin Y, Fiore M. Targeting tissue factor pathway inhibitor with concizumab to improve hemostasis in patients with Glanzmann thrombasthenia: an in vitro study. J Thromb Haemost. 2024 Sep;22(9):2589-2600. doi: 10.1016/j.jtha.2024.05.033. Epub 2024 Jun 14.
PubMed 38880178
Study at a glance
From the registry record, last updated by the sponsor on 26 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Targeting TFPI With Concizumab to Improve Haemostasis in Glanzmann Thrombasthenia Patients: an in Vitro Study
- ClinicalTrials.gov ID
- NCT06234813
- Acronym / sponsor ID
- GLAT / CHUBX 2021/44
- Conditions
- Glanzmann Thrombasthenia
- Keywords
- Concizumab, Hemostatic capacity, Glanzmann Thrombasthenia
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 20 participants (actual)
- Lead sponsor
- University Hospital, BordeauxUniversity, hospital or other
- Study start
- 6 Apr 2023 (actual)
- Primary completion
- 17 Jul 2023 (actual)
- Study completion
- 17 Jul 2023 (actual)
- First posted
- 31 Jan 2024 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Glanzmann thrombasthenia is a rare genetic disorder caused by the absence or the dysfunction of the main receptor present on the surface of platelets, integrin αIIbβ3 or GPIIb-IIIa.
The lack of this protein on the surface of platelets no longer allows these blood cells to bind to each other. This binding corresponds to the process of platelet aggregation.
Generally, local measures will control nasal and superficial bleeding whereas platelet transfusions are used to control or prevent life-threatening.
The main complication of this treatment is the risk of developing anti-αIIbβ3 antibodies directed against the absent protein and platelet transfusion therapy can become ineffective.
Activated recombinant factor VII (rFVIIa) provides an alternative treatment for GT patients who develop such antibodies. However, this therapy has a short duration of efficacy, requiring repeated intravenous administrations every 2 to 3 hours.
There is a new treatment, Concizumab, which has not yet been marketed. This treatment acts on TFPI (tissue factor pathway inhibitor). TFPI is a protein that occurs naturally in the body and prevents blood cells from binding to each other.
Concizumab works by blocking TFPI, which may allow sufficient clotting to prevent bleeding.
This treatment could replace recombinant activated factor VII (rFVIIa) because it has the advantage of a much longer duration of efficacy (about 3 days) and is administered subcutaneously.
Detailed description
This is in vitro research. The treatment will be tested on blood samples. This will allow us to evaluate in vitro the ability of Concizumab to restore coagulation compared to the usual treatments of platelet transfusions and recombinant activated factor VII (rFVIIa).
This is a single-center study conducted at the Bordeaux University Hospital, which included 10 with Glanzmann thrombasthenia patients and 10 healthy donors over a period of 12 months.
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Glanzmann Thrombasthenia Group | Experimental | Other: Clot formation in whole blood under flow in a microfluidic flow chamber coated with tissue factor and collagen, Other: : PRP viscoelastic changes under clot formation measured by thromboelastometry using RoTEM, Other: Thrombin Generation Assay (TGA) in PRP using TF trigger, Other: Global fibrinolytic capacity in PRP using reagents for in vitro triggering of the clot and its lysis, Other: ConcizumabPatient with a clear diagnosis of Glanzmann Thrombasthenia, whatever the subtype of disease |
| Healthy donors | Active comparator | Other: Clot formation in whole blood under flow in a microfluidic flow chamber coated with tissue factor and collagen, Other: : PRP viscoelastic changes under clot formation measured by thromboelastometry using RoTEM, Other: Thrombin Generation Assay (TGA) in PRP using TF trigger, Other: Global fibrinolytic capacity in PRP using reagents for in vitro triggering of the clot and its lysisHealthy donor without haemorrhagic ant thrombotic medical history |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (11 listed)
- Patient ≥18 years old
- Patient with a clear diagnosis of Glanzmann Thrombasthenia (GT), whatever the subtype of disease
- Affiliated person or beneficiary of a social security scheme.
- Free, informed and written consent signed by the participant, and the investigator (at the latest on the day of inclusion and before any examination required by the research)
- Healthy donor ≥ 18 years old
Key exclusion criteria (6 listed)
- Patient who has taken aspirin or a nonsteroidal anti-inflammatory medication within the previous 10 days
- Patient who has received a platelet transfusion or recombinant activated factor VII hemostatic treatment within the previous 7 days
- Patient who participated in another interventional study involving a drug within 30 days of entering this protocol
- Psychiatric, social or behavioral condition judged to be non-compatible with the respect of the protocol
- Adult protected by the law
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Clot formation in whole blood under flow in a microfluidic flow chamber coated with tissue factor and collagenTTAS (single measurements) Clot formation in whole blood under flow (2000 s-1) in a microfluidic flow chamber coated with tissue factor and collagen (T-TAS with AR chip) 1. 500 µL of whole blood for each point; 2. 7 points for each condition; 3. Around 4 mL of whole blood will be needed for each patient or healthy subject; 4. Values for Area Under the Curve (Aritrary Unit), Occlusion Starting Time (min), Occlusion Time (min.) will be reported. | Other | Glanzmann Thrombasthenia Group, Healthy donors |
| : PRP viscoelastic changes under clot formation measured by thromboelastometry using RoTEMROTEM (single measurements) 1. ROTEM cups will be added * 20 µL calcium reagent (STARTEM) * 20 µL of 2,940-fold prediluted r-ExTEM reagent (50,000 fold dilution relative to 340 µL in the cup) added * 300 µL spiked PRP at 250 G/L (2.5 mL of PRP/patient) 2. Values for clot time (CT sec, clot formation time (CFT) sec, maximum clot formation (mm) will be reported. | Other | Glanzmann Thrombasthenia Group, Healthy donors |
| Thrombin Generation Assay (TGA) in PRP using TF triggerTGA (single measurements) 1. The following will be added to well: * 20 uL of PRP-Reagent * 80 uL of spiked PRP (600 µL/patient at 100 G/L) * 20 uL FluCa 2. Values for thrombin activity versus time and the derived parameters incl. lag-time (min), time to peak (min), time to peak (min), ETP (Arbitrary Unit) will be reported. | Other | Glanzmann Thrombasthenia Group, Healthy donors |
| Global fibrinolytic capacity in PRP using reagents for in vitro triggering of the clot and its lysisGlobal fibrinolytic capacity (Lysis Timer) in 100 µL of PRP (250 G/L) using reagents for in vitro triggering of the clot (thrombin and calcium) and its lysis (tissue-plasminogenactivator (t-PA). Around 1 mL of PRP in total Lysis time in min | Other | Glanzmann Thrombasthenia Group, Healthy donors |
| ConcizumabThrombin generation assay (TGA), microchip flow-chamber assay (T-TAS, rotational thromboelastometry and global fibrinolytic capacity to investigate and compare the effects of mixing concizumab (200, 1000 and 4000 ng/mL) with the main bleed treatment options for persons with GT | Other | Glanzmann Thrombasthenia Group |
Primary outcome
Effects of mixing concizumab compared with the main bleed treatment options for persons with GT
Time frame: One point at the inclusion
The samples will be analysed by measurement of in vitro hemostatic capacity : * Clot formation in whole blood under flow (2000 s-1) in a microfluidic flow chamber coated with tissue factor and collagen. Values for Area Under the Curve (Aritrary Unit), Occlusion Starting Time (min), Occlusion Time (min.) will be reported * PRP viscoelastic changes under clot formation measured by thromboelastometry. Values for clot time (sec), clot formation time (sec), maximum clot formation (mm) will be reported * Thrombin Generation Assay in PRP using tissue factor trigger. Values for thrombin activity versus time and the derived parameters incl. lag-time (min.), time to peak (min), time to peak (min), ETP (Arbitrary Unit) will be reported * Global fibrinolytic capacity (Lysis Timer in min) in whole blood using reagents for in vitro triggering of the clot and its lysis
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 26 May 2026.
- Results publication: PubMed 38880178Dubut J, Goin V, Derray C, Huguenin Y, Fiore M. Targeting tissue factor pathway inhibitor with concizumab to improve hemostasis in patients with Glanzmann thrombasthenia: an in vitro study. J Thromb Haemost. 2024 Sep;22(9):2589-2600. doi: 10.1016/j.jtha.2024.05.033. Epub 2024 Jun 14.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Mathieu FIORE principal investigator
University Hospital, Bordeaux
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Clot formation in whole blood under flow in a microfluidic flow chamber coated with tissue factor and collagen, : PRP viscoelastic changes under clot formation measured by thromboelastometry using RoTEM and Thrombin Generation Assay (TGA) in PRP using TF trigger in people with Glanzmann Thrombasthenia, run by University Hospital, Bordeaux at 1 site 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 11 inclusion and 6 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 26 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site 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?
Effects of mixing concizumab compared with the main bleed treatment options for persons with GT (time frame: One point at the inclusion). 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 NCT06234813, 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 26 May 2026.