Immunological Aspect of Thrombotic Thrombocytopenic Purpura (TTP)

NCT06945861 | Recruiting

• 2 other identifiers: 2022/308/OBIDRCB : 2023-A00455-40
• Study Type: observational
• Target: 44
• Locations: 1 country
• Sites: 1

Brief Summary

The general objective of the proposed project is to characterise phenotypically and functionally ADAMTS13-specific memory B lymphocytes and autoreactive T lymphocytes, in particular follicular helper T lymphocytes, in the acute phase of the disease, but also during its progression after treatment. The aim is to highlight their contribution to the initial pathogenic process, their evolution under treatment, and also their involvement in patients who are refractory to immunosuppressive therapies and during relapses. The aim of this project is to identify early phenotypic or functional parameters that are predictive of relapse and that can be used for personalised optimisation of treatment to maintain remission.

Conditions

Thrombotic Thrombocytopenic Purpura (TTP)

Outcome Measures

Primary Outcomes (2)

• Identifying the presence of circulating autoreactive T lymphocytes

  Identifying the presence of circulating autoreactive T lymphocytes in patients with TTP using the ELISPOT technique (Demonstration of spots indicating the presence of gamma interferon-producing T lymphocytes)

  At enrollment visit, Month 3, Month 6 and month 12

• Identify the presence of circulating autoreactive B lymphocytes

  Identifying the presence of circulating autoreactive B lymphocytes in patients with TTP using the ELISPOT technique (Demonstration of IL-21 spots and specific B lymphocytes producing anti-ADAMTS13 antibodies in response to the ADAMTS13 antigen)

  At enrollment visit, Month 3, Month 6 and month 12

Secondary Outcomes (8)

• Study quantitative variations in circulating autoreactive T lymphocytes

  At enrollment visit, Month 3, Month 6 and month 12

• Study quantitative variations in circulating autoreactive B lymphocytes

  At enrollment visit, Month 3, Month 6 and month 12

• Determine the phenotypic characteristics of circulating autoreactive T lymphocytes

  At enrollment visit, Month 3, Month 6 and month 12

• Determine the phenotypic characteristics of circulating autoreactive B lymphocytes

  At enrollment visit, Month 3, Month 6 and month 12

• Quantitative variations in circulating autoreactive T lymphocytes

  At enrollment visit, Month 3, Month 6 and month 12

Study Arms (4)

Group 1: patients in the acute phase of TTP

Consultation or hospitalisation when TTP is diagnosed, before treatment is initiated

Groupe 2 : patient in durable remission with ADAMTS13 activity > 10%.

Follow-up consultation

Groupe 3 : patient in remission with ADAMTS13 activity < 10%.

Follow-up consultation before initiation of pre-emptive treatment

Group 4: relapsing patients

Consultation or hospitalisation at the time of relapse, before treatment is initiated

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

patients with thrombotic thrombocytopenic purpura, whatever the stage of diagnosis (acute phase, lasting remission or not, relapse)

You may qualify if:

• age over 18
• patients with TTP at any stage of diagnosis (acute phase, lasting remission or not, relapse)
• patients undergoing internal medicine at Rouen University Hospital
• people who have read and understood the information letter
• membership of a social security scheme

You may not qualify if:

• \- a person deprived of liberty by an administrative or judicial decision or a person placed under court protection/guardianship or guardianship

Sponsors & Collaborators

• University Hospital, Rouen: lead

Study Sites (1)

University Rouen Hospital,

Rouen, 76031, France

RECRUITING

Biospecimen

Retention: SAMPLES WITHOUT DNA

The aim of whole blood sampling is to characterise phenotypically and functionally the ADAMTS13-specific memory B lymphocytes and autoreactive T lymphocytes, in particular follicular helper T lymphocytes, in the acute phase of the disease, but also during its progression after treatment.

MeSH Terms

Conditions

Purpura, Thrombotic Thrombocytopenic

Condition Hierarchy (Ancestors)

Purpura, Thrombocytopenic; Purpura; Blood Coagulation Disorders; Hematologic Diseases; Hemic and Lymphatic Diseases; Thrombotic Microangiopathies; Thrombocytopenia; Blood Platelet Disorders; Cytopenia; Thrombophilia; Hemorrhage; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Skin Manifestations; Signs and Symptoms

Central Study Contacts

David DM MALLET, Director

CONTACT

02 32 88 82 65; david.mallet@chu-rouen.fr

Vincent VF FERRANTI, ARC

CONTACT

02 32 88 82 65; vincent.ferranti@chu-rouen.fr

Study Design

• Study Type: observational
• Observational Model: CASE ONLY
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: April 7, 2025
• First Posted: April 25, 2025
• Study Start: May 11, 2023
• Primary Completion (Estimated): May 10, 2027
• Study Completion (Estimated): May 11, 2028
• Last Updated: May 4, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

FR (1)