How iron affects the immune system in HHT

Immunological Effects of Iron Supplementation in HHT Disease

This study will test whether giving iron changes T-cell counts and other immune markers in adults with HHT.

Quick facts

• Phase: Not applicable
• Study type: Interventional
• Enrollment: 155 (estimated)
• Ages: 18 Years to 99 Years
• Sex: All
• Sponsor: Hospices Civils de Lyon (Academic / other)
• Locations: 1 site (Bron, Rhone)
• Trial ID: NCT07111598 on ClinicalTrials.gov

What this trial studies

This study compares immune cell measures in adults with genetically confirmed HHT grouped by iron status and recent iron treatment. Participants undergo blood tests at enrollment (day 0) and again at three months to measure complete blood count, ferritin, inflammatory markers, and lymphocyte subsets including T cells. Groups include patients with normal ferritin and no recent iron therapy, patients with normal ferritin but recent iron therapy or transfusion, and patients with low ferritin without recent supplementation. The design examines whether iron repletion or recent iron exposure is associated with changes in T-lymphocyte counts and other immunological markers.

Who should consider this trial

Good fit: Adults with HHT who meet Curaçao criteria or have a pathogenic ENG/ACVRL1/MADH4 mutation, are enrolled in the CIROCO cohort, and have the required recent laboratory tests are eligible.

Not a fit: People who do not have iron deficiency, who already have stable iron treatment, or who do not meet the inclusion criteria are unlikely to receive direct benefit from participation.

Why it matters

Potential benefit: If successful, the results could show that correcting iron deficiency improves T-cell counts and might reduce infection risk in people with HHT.

How similar studies have performed: Some studies outside of HHT link iron deficiency to lower lymphocyte counts, but the specific effect of iron on T-cell lymphopenia in HHT remains relatively untested.

Eligibility criteria

Inclusion Criteria:

* For all three groups:

  * Adult patient diagnosed with HHT (meeting 3 or 4 Curaçao criteria).
  * Documented pathogenic mutation in one of the following genes: ENG, ACVRL1, or MADH4.
  * Patient enrolled in the CIROCO cohort.
  * Written informed consent freely given and signed by the patient.
  * Patient covered by a social security scheme or equivalent.
  * Routine biological follow-up for HHT performed within the 15 days preceding the inclusion visit (complete blood count, reticulocytes, ferritin, CRP, calcium, phosphorus).
* Specific to Group 1:

  * Ferritin \> 25 µg/L
  * No iron supplementation (oral or intravenous) in the past 3 months
  * No red blood cell transfusion in the past 3 months
* Specific to Group 2:

  * Ferritin \> 25 µg/L
  * Ongoing oral iron therapy, or at least one intravenous iron infusion, or at least one red blood cell transfusion within the past 3 months
* Specific to Group 3:

  * Ferritin \< 25 µg/L
  * No iron supplementation (oral or intravenous) in the past 3 months
  * No red blood cell transfusion in the past 3 months

Exclusion Criteria:

* Patients with hemoglobin levels \< 90 g/L.
* Patients with active cancer or recent cancer remission (\< 3 months) that may alter the immune profile.
* Patients with an active infection or recent infection recovery (\< 3 months) that may alter the immune profile.
* Patients with an autoimmune or autoinflammatory disease, either active or recently treated (\< 3 months), requiring immunosuppressive therapy and potentially altering the immune profile.
* Pregnant, postpartum, or breastfeeding women.
* Minors.
* Individuals deprived of liberty by judicial or administrative decision.
* Individuals undergoing psychiatric care.
* Individuals admitted to a healthcare or social institution for reasons other than research participation.
* Adults under legal protection (guardianship, curatorship).
* Individuals participating in another interventional clinical trial with an exclusion period still in effect at the time of pre-inclusion.

Where this trial is running

Bron, Rhone

• Hôpital Femme-Mère-Enfant — Bron, Rhone, France (Recruiting)

Study contacts

• Study coordinator: Alexandre Guilhem, MD

Conditions Hereditary Haemorrhagic Telangiectasia; Hereditary haemorrhagic telangiectasia; iron supplementation; lymphopenia