ClinicalTrials.gg
RecruitingNCT03541525GR-ExUpdated Sep 9, 2026

Pathophysiological Explorations of Red Blood Cells

An observational study in Red Blood Cell Disorder, sponsored by Imagine Institute. Recruiting at 25 sites in 3 countries. Per ClinicalTrials.gov, last updated 2026-09-09.

Sponsored by Imagine Institute · Observational

From the registry’s dates

  • Started Oct 2017; still recruiting 9 years later.
Study type
Observational
Model
Cohort
Time perspective
Prospective
Enrollment
3,750
Sex
All
01

Study summary

GR-Ex is a program labelled by Labex (Laboratory of Excellence) by the French Ministry of Higher Education and Research. This program aims to develop the means to improve knowledge in the physiology and pathologies of erythropoiesis, red blood cells and iron metabolism, and to develop new therapeutic protocols capable of providing added value in terms of innovation.

02

Conditions studied

  • Red Blood Cell Disorder
03

In context

Lead sponsor

Imagine Institute is the lead sponsor of 31 studies on the registry; 15 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
Child (0–17), Adult (18–64), Older adult (65+)
Sexes eligible
All
Accepts healthy volunteers
Yes
Sampling method
Probability sample

Study population

Inclusion of patients affected by red blood cell disorder and their non affected relatives

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • To be affected or have a family history of disease bound to the red blood cell,
  • For adult subjects, have signed an form,
  • For minor or major under legal safeguard subjects, the form must be signed by both parents (for minors) or by the legal representative,
  • Be affiliated to health insurance.

Exclusion criteria

Exclusion Criteria:

  • Being deprived of freedom
Terms in these criteria, in plain language(1)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

05

Study design

Observational model
Cohort
Time perspective
Prospective
Enrollment
3,750 participants (estimated)
Patient registry
No
Biospecimen retention
Samples with dna

Groups and cohorts

  • Affected patients

    Biological samples of blood for all patients. Biological samples of saliva, surgical remainder (skin, tumor, kidney,....), saliva, urine, hair.

    Other: Biological sampling

  • Non affected relatives

    Biological samples of blood for all relatives.

    Other: Biological sampling

Interventions

  • OtherBiological sampling

    Biological samples including blood, surgical remainder, urine,...

06

What researchers measure

Primary outcomes

  1. Innovative markers of spleen fonctionality

    Retention rate (%) of red blood cells using Microsphiltration compared with non affected subjects

    Time frame: 20 years

  2. Quantification of inflammation in sickle cell disease

    Activation rate of circulating mastocytes (%)

    Time frame: 20 years

  3. Markers of post-artesunate hemolysis

    Concentration of pitted red blood cells at day 3

    Time frame: 20 years

  4. Correlation between transfusion yield and the storage of red blood cell bags

    Increasing in haemoglobin concentration at 6 hours post transfusion

    Time frame: 20 years

  5. Efficiency of Phosphodiesterase inhibitor on neutrophil adhesion in Sickle cell disease

    Proportional change in adhesion rate (%) of neutrophils measured in the peripheral blood before and after treatment with phosphodiesterase inhibitors

    Time frame: 20 years

  6. Quantification of mitochondria removal during erythropoiesis in SDC patients, consequences on the mature RBC

    Mitochondria rate and level of ROS in RBC measured by Flow Cytometry

    Time frame: 20 years

  7. Study of iron metabolism in Diamond-Blackfan Anemia patients

    Dosage of iron metabolism parameters

    Time frame: 20 years

07

Study locations

22 of 25 sites recruiting
08

References and documents

Publications

  • Sissoko A, Cisse A, Duverdier C, Marin M, Dumas L, Manceau S, Maitre B, Eckly A, Fricot-Monsinjon A, Roussel C, Ndour PA, Dussiot M, Dokmak S, Aussilhou B, Dembinski J, Sauvanet A, Paye F, Lesurtel M, Cros J, Wendum D, Tichit M, Hardy D, Capito C, Allali S, Buffet P. Clearance of pathogenic erythrocytes is maintained despite spleen dysfunction in children with sickle cell disease. Am J Hematol. 2024 Dec;99(12):2267-2278. doi: 10.1002/ajh.27481. Epub 2024 Sep 17. PubMed 39286963 ↗
  • Qiang Y, Sissoko A, Liu ZL, Dong T, Zheng F, Kong F, Higgins JM, Karniadakis GE, Buffet PA, Suresh S, Dao M. Microfluidic study of retention and elimination of abnormal red blood cells by human spleen with implications for sickle cell disease. Proc Natl Acad Sci U S A. 2023 Feb 7;120(6):e2217607120. doi: 10.1073/pnas.2217607120. Epub 2023 Feb 2. PubMed 36730189 ↗
09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Sep 9, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT03541525
Lead sponsor
Imagine Institute
Responsible party
Sponsor
First posted
May 30, 2018
Start date
Oct 16, 2017
Primary completion
Oct 15, 2037 (estimated)
Completion
Oct 15, 2037 (estimated)
Last update
Sep 9, 2026

Study contacts

Sandra Manceau, PhD
Contact
sandra.manceau@aphp.fr
+33171196435
Pierre Buffet, MD
Contact
pabuffet@gmail.com
+33142754456
Olivier Hermine, MD, PhD
study director · Assistance Publique - Hôpitaux de Paris

Oversight

FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Interested in this study?

Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.

Contact study team

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Start the discussion