Sickle Cell Disease (SCD)MegaDrepNCT06850337
Megakaryocyte Heterogeneity in Sickle Cell Disease
An observational study of Sickle Cell Disease (SCD), run by Centre Hospitalier Universitaire de la Guadeloupe at 1 site in Guadeloupe.
Trial summary
Sickle cell disease (SCD) is characterized by chronic hemolytic anemia, painful crisis called vaso-occlusive crisis (VOC) and chronic inflammation. Activated platelets of SCD patients participated to both chronic inflammation and painful VOC. Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Sickle Cell Disease (SCD)
- How many people
- 100 participants
- Where
- 1 siteGuadeloupe
- Study dates
- Jul 2025to Mar 2027
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
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
Study population: Patients with sockle celle disease are patients who come for their disease. Control group are patients who come at the University hospital of Guadeloupe (Pointe à Pitre), for hip or knee replacement and will do not suffer from chronic disease.
Who may be able to join
- patients with SS or SC SCD
- diagnosis of SCD performed by electrophoresis or HPLC in a reference laboratory for hemoglobinopathies
- patients older than 18 years at inclusion
- clinically in a steady state at inclusion (without complication in the last month and without transfusion in the three last months)
- patient followed up for SCD at the sickle cell center of Guadeloupe (University hospital of Guadeloupe, Pointe à Pitre)
- patients who will provide written informed consent in accordance with the Declaration of Helsinki
- patients affiliated to national social security
- the control group (AA subjects) will be patients older than 18 years old who come at the University hospital of Guadeloupe, (Pointe à Pitre) for hip or knee replacement and will do not suffer from chronic disease.
Who cannot join
- patients younger than 18 years old
- patients with hemoglobinopathy other than SS and SC SCD
- patients with a transfusion therapy or on bleeding therapy for less than three months
- patients no affiliated to national social security
- pregnant or breastfeeding patients
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Guadeloupe1 site
Chu de La Guadeloupe
Pointe-à-Pitre, 97159
Valérie Hamony Soter, +590590934677, valerie.soter@chu-guadeloupe.fr
Mélanie Petapermal, melanie.petapermal@chu-guadeloupe.fr
About this study
Official title: Characterization of Megakaryocytic Subpopulations and the "Immune" Phenotype of Platelets of the Sickle Cell Disease Patient
Sickle cell disease (SCD) is characterized by chronic hemolytic anemia, painful crisis called vaso-occlusive crisis (VOC) and chronic inflammation. Activated platelets of SCD patients participated to both chronic inflammation and painful VOC. Platelets are anucleated cells from the fragmentation of megakaryocytes in bone marrow.
The main aim of this study is to characterize the distribution of the different megakaryocyte subpopulations of sickle cell disease patients SS and SC and in particular the "immune" megakaryocytes CD148+CD48+ and to compare it with the platelet phenotype.
Read the detailed description
Platelets are activated in all sickle cell disease patients at baseline with higher expression of selective P (CD62P). Platelets provide a major function in primary hemostasis by the formation of the platelet clot and also participate in coagulation through the formation of an electro-negative phospholipid surface essential to the enzymes of the coagulation cascade. It is now known that platelets are also immune cells that are able to secrete pro-inflammatory cytokines (TGF beta, IFN gamma), that they express certain Toll-like receptors (TLR4) and the inflammasome NLRP3 leading to the activation of caspase-1. Several teams, including ours, have shown that inflammasome and/or caspase-1 can be activated in an infectious context, particularly viral (dengue fever, COVID) and inflammatory (chronic inflammatory bowel diseases, etc.).
Platelets are anucleated cells from the fragmentation of megakaryocytes. Their protein profile is therefore the result of bone marrow differentiation of megakaryocytes. Recently, it has been shown a cellular heterogeneity within megakaryocytes including immune megakaryocytes whose proportion can significantly increase in stress and inflammation condition. It is not clear whether these immune megakaryocytes that could behave as antigen-presenting cells are capable of producing blood platelets.
We wonder whether sickle cell disease patients have a different proportion of these immune megakaryocytes compared to healthy subjects and whether their activated blood platelets carry specific markers of these immune megakaryocytes.
SCD patients will be recruited in the active file of the sickle cell center of Guadeloupe. Two groups of patients will be constituted: SS patients and SC patients. The control group will be composed of patients who come for hip or knee replacement and do not suffer from chronic disease. Only one blood and bone marrow collection will be realized during the study.
- Conditions
- Sickle Cell Disease (SCD)
- Keywords
- sickle cell disease, immune megakaryocytes, platelets, CD48, CD148
- Medical subject headings
- Anemia, Sickle Cell
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| SS patients | patients with SS sickle cell disease | |
| SC patients | patients with SC sickle cell disease | |
| control group AA | patient without sickle cell disease (AA hemoglobin) |
What is being measured
The primary outcome is the main question the study is designed to answer.
proportion of immune megakaryocytes CD148+CD48+ in bone marrow
The primary outcome will be the evaluation of the proportion of immune megakaryocytes CD148+CD48+ in bone marrow of sickle cell disease patients in comparison to control group.
Measured: 24 months
Secondary outcomes (1)
platelet phenotype
The secondary outcomes are to compare the platelet phenotype between the three groups of patients, including the proportion of CD148+CD48+ platelets, to study the activation of this platelet subpopulation (expression of CD62P) and establish whether there is a relationship between the proportion of immune megakaryocytes in the bone marrow and the proportion of CD148+CD48+ platelets in the blood.
Measured: 24 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted27 Feb 2025
- Study startJul 2025 (estimated)
- Primary completionMar 2027 (estimated)
- Study completionMar 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Sickle Cell Disease (SCD)Studies of the same condition, open and under way.
- 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
- Observational
- Observational model
- Other
- Time perspective
- Prospective
- Enrolment
- 100 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Centre Hospitalier Universitaire de la Guadeloupe
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Veronique Baccini, MD PhD, Study chair, CHU de la Guadeloupe
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06850337
- Sponsor's protocol ID
- PAP_RIPH2_2024/04
- Other IDs
- 2024-A01093-44
- Acronym
- MegaDrep
- Status last verified
- May 2025
- First submitted
- 24 Feb 2025
- Last updated
- 25 May 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 25 May 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Characterization of Megakaryocytic Subpopulations and the "Immune" Phenotype of Platelets of the Sickle Cell Disease Patient
- ClinicalTrials.gov ID
- NCT06850337
- Acronym / sponsor ID
- MegaDrep / PAP_RIPH2_2024/04
- Conditions
- Sickle Cell Disease (SCD)
- Keywords
- sickle cell disease, immune megakaryocytes, platelets, CD48, CD148
- Study type
- Observational
- Recruitment status
- Not yet recruiting
- Enrolment
- 100 participants (estimated)
- Lead sponsor
- Centre Hospitalier Universitaire de la GuadeloupeUniversity, hospital or other
- Study start
- Jul 2025 (estimated)
- Primary completion
- Mar 2027 (estimated)
- Study completion
- Mar 2027 (estimated)
- First posted
- 27 Feb 2025 (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.
Sickle cell disease (SCD) is characterized by chronic hemolytic anemia, painful crisis called vaso-occlusive crisis (VOC) and chronic inflammation. Activated platelets of SCD patients participated to both chronic inflammation and painful VOC. Platelets are anucleated cells from the fragmentation of megakaryocytes in bone marrow.
The main aim of this study is to characterize the distribution of the different megakaryocyte subpopulations of sickle cell disease patients SS and SC and in particular the "immune" megakaryocytes CD148+CD48+ and to compare it with the platelet phenotype.
Detailed description
Platelets are activated in all sickle cell disease patients at baseline with higher expression of selective P (CD62P). Platelets provide a major function in primary hemostasis by the formation of the platelet clot and also participate in coagulation through the formation of an electro-negative phospholipid surface essential to the enzymes of the coagulation cascade. It is now known that platelets are also immune cells that are able to secrete pro-inflammatory cytokines (TGF beta, IFN gamma), that they express certain Toll-like receptors (TLR4) and the inflammasome NLRP3 leading to the activation of caspase-1. Several teams, including ours, have shown that inflammasome and/or caspase-1 can be activated in an infectious context, particularly viral (dengue fever, COVID) and inflammatory (chronic inflammatory bowel diseases, etc.).
Platelets are anucleated cells from the fragmentation of megakaryocytes. Their protein profile is therefore the result of bone marrow differentiation of megakaryocytes. Recently, it has been shown a cellular heterogeneity within megakaryocytes including immune megakaryocytes whose proportion can significantly increase in stress and inflammation condition. It is not clear whether these immune megakaryocytes that could behave as antigen-presenting cells are capable of producing blood platelets.
We wonder whether sickle cell disease patients have a different proportion of these immune megakaryocytes compared to healthy subjects and whether their activated blood platelets carry specific markers of these immune megakaryocytes.
SCD patients will be recruited in the active file of the sickle cell center of Guadeloupe. Two groups of patients will be constituted: SS patients and SC patients. The control group will be composed of patients who come for hip or knee replacement and do not suffer from chronic disease. Only one blood and bone marrow collection will be realized during the study.
Study design
- Observational model
- Other
- Time perspective
- Prospective
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| SS patients | – | –patients with SS sickle cell disease |
| SC patients | – | –patients with SC sickle cell disease |
| control group AA | – | –patient without sickle cell disease (AA hemoglobin) |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
- Study population
- Patients with sockle celle disease are patients who come for their disease. Control group are patients who come at the University hospital of Guadeloupe (Pointe à Pitre), for hip or knee replacement and will do not suffer from chronic disease.
Key inclusion criteria (8 listed)
- patients with SS or SC SCD
- diagnosis of SCD performed by electrophoresis or HPLC in a reference laboratory for hemoglobinopathies
- patients older than 18 years at inclusion
- clinically in a steady state at inclusion (without complication in the last month and without transfusion in the three last months)
- patient followed up for SCD at the sickle cell center of Guadeloupe (University hospital of Guadeloupe, Pointe à Pitre)
Key exclusion criteria (5 listed)
- patients younger than 18 years old
- patients with hemoglobinopathy other than SS and SC SCD
- patients with a transfusion therapy or on bleeding therapy for less than three months
- patients no affiliated to national social security
- pregnant or breastfeeding patients
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
proportion of immune megakaryocytes CD148+CD48+ in bone marrow
Time frame: 24 months
The primary outcome will be the evaluation of the proportion of immune megakaryocytes CD148+CD48+ in bone marrow of sickle cell disease patients in comparison to control group.
1 secondary outcome
platelet phenotype
Time frame: 24 months
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 25 May 2025.
- 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.
Veronique Baccini, MD PhD study chair
CHU de la Guadeloupe
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Sickle Cell Disease (SCD), run by Centre Hospitalier Universitaire de la Guadeloupe at 1 site in Guadeloupe.
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 8 inclusion and 5 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: opening soon, as of the sponsor's last update on 25 May 2025. 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 Guadeloupe. 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?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Valérie Hamony Soter (+590590934677, valerie.soter@chu-guadeloupe.fr), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
proportion of immune megakaryocytes CD148+CD48+ in bone marrow (time frame: 24 months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 25 May 2025.