ClinicalTrials.gov record NCT05089227

Efficacy of Prolonged Anticoagulation for Primary Prevention of Venous Thromboembolic Disease in Autoimmune Hemolytic Anemia: a Prospective, Phase II, Randomized, Multicenter Study

Record copied from ClinicalTrials.gov: Oct 10, 2026AI summaries generated: Aug 22, 2026

Efficacy of Prolonged Anticoagulation for Primary Prevention of Venous Thromboembolic Disease in Autoimmune Hemolytic Anemia: a Prospective, Phase II, Randomized, Multicenter Study

StatusRecruitingThe study is currently enrolling participants. Only the study team can say whether a particular person can join.
Study typeInterventionalA study in which researchers assign participants to one or more interventions, such as a drug, procedure, device, behavioural programme or other approach, to measure their effects.
PhasePhase 2A study that tests whether a treatment has the intended effect and continues to check safety, usually in a larger group than phase 1.
Age18 years old and older
SexAll
LocationFrance
AI summaryWhat this study is about, in plain languageShow ▾Hide ▴

AI-written from the registry record, not the study's own wording. May contain errors or omissions. Check the registry text on this page and the original record ↗ before acting on it.

This phase II randomized study compares two approaches to preventing blood clots in adults with autoimmune hemolytic anemia (AIHA) who are newly diagnosed or in relapse. One group receives in-hospital prophylactic heparin followed by oral apixaban to complete 12 weeks of prophylaxis; the other receives in-hospital prophylactic heparin only and no prolonged anticoagulation. The study records confirmed deep vein thrombosis and pulmonary embolism up to 24 weeks after randomization. Blood tests tied to hemolysis are collected in both groups.

What it is studying. The study tests whether prolonging preventive anticoagulation during the 12-week high-risk period after AIHA diagnosis or relapse (hospital heparin followed by apixaban) versus stopping prophylaxis after hospitalization affects the occurrence of clinically confirmed venous thromboembolic events (deep vein thrombosis and pulmonary embolism) within 24 weeks.

What the researchers hope to learn. To determine whether prolonged prophylactic anticoagulation during the 12-week high-risk period after AIHA diagnosis or relapse influences the occurrence of clinical venous thromboembolic events (DVT and PE).

What this study is about

The study's own summary, as published on ClinicalTrials.gov. Underlined terms have a short explanation.

Autoimmune hemolytic anemia (AIHA) is a rare autoimmune disease (incidence <1/100,000 population) responsible for the destruction of red blood cells by the host immune system, notably through the action of autoantibodies. Apart from complications related to anemia, the occurrence of venous thromboembolism (VTE) in this population is frequent, estimated at 20-27%. The risk of VTE is highest during the period of hemolysis, especially during the first 3 months after the diagnosis of AIHA. This risk is 7.5 [4.7; 12.0] times greater than in the general population. No clinical predictive factor for VTE was identified and the usual factors (cancer, previous VTE, bed rest >3 days, surgery, age >70 years, heart or respiratory failure, myocardial infarction, stroke, obesity, hormone replacement therapy) were not considered. Several biological risk factors have been suggested (depth of anemia, bilirubin level, leukocyte count, antiphospholipid antibodies) but have not been confirmed in other studies. AIHA is therefore a risk factor for VTE in its own right, and the National Diagnostic and Care Protocol (NDCP) recommends the implementation of VTE prevention during acute hemolysis (Grade C). However, the value of this prophylaxis has never been prospectively evaluated and its duration is empirical. In practice, low-molecular-weight heparin (LMWH) is generally used during "flare-ups" of AIHA (diagnosis and relapse) in hospitalized patients, but is rarely continued beyond the hospital phase when VTE also occurs in ambulatory patients. Thus, we hypothesize that prolonged preventive anticoagulation during the 12-week risk period following diagnosis or relapse of AIHA could decrease the incidence of VTE. In orthopedic surgery, this strategy has been proven to decrease VTE from 50% to 10-15%. In certain high-risk medical situations, prolonged prophylaxis with apixaban has been shown to decrease the occurrence of VTE from 10.2% to 4.2% in solid cancers4 and from 4-11% to 2% in myeloma.

Interventions being studied

Being studied in this trial does not mean the treatment or procedure is approved or available for this condition.

Drug
  • treatment "intervention"
  • treatment "standard"
Biological
  • biological assessment

Eligibility

The criteria exactly as listed on ClinicalTrials.gov. Only the study team can say whether they apply to you.

Inclusion criteria

  • Patient aged ≥ 18 years
  • Patient with a diagnosis of primary or secondary autoimmune hemolytic anemia (AIHA) (infections, hematologic diseases, systemic diseases), according to the following criteria:
  • Hemoglobin <12 g/dL
  • and decreased haptoglobin (<0.4 g/L)
  • and positive direct antiglobulin test (direct Coombs test) (IgG +/- C3d)
  • Patient newly diagnosed or relapse
  • Patient with an estimated life expectancy of more than 6 months
  • Patient who provided free, written and informed consent

Exclusion criteria

  • Patients with immediate symptomatic VTE, confirmed by appropriate complementary examinations (venous Doppler of the lower limbs, thoracic angioscanner or pulmonary scintigraphy).
  • Patients on curative anticoagulation (venous thromboembolic disease, atrial fibrillation)
  • Patient on dual antiaggregation treatment
  • Patient with active bleeding
  • Patient with a known condition or lesion at risk of bleeding
  • Patient with ischemic stroke with hemorrhagic transformation within 6 months prior to inclusion
  • Patient on preventive anticoagulation for 14 days or more
  • Patient with a contraindication to apixaban:
  • Known hypersensitivity to the molecule or to any of the excipients,,
  • thrombocytopenia <100 G/L,
  • kidney failure (glomerular filtration rate < 30 ml/min/1.73m²)
  • Active liver disease (liver failure defined as Factor V <50% or INR >1.5, ALT elevation >2 times the upper limit of normal)
  • Patients receiving concomitant CYP3A4 inducers (rifampin, phenytoin, carbamazepine, phenobarbital, St. John's Wort) or CYP3A4 inhibitors (azole antifungals, HIV protease inhibitors), if these therapies cannot be discontinued or modified
  • Patients with a contraindication to enoxaparin:
  • allergy to the drug
  • history of heparin-induced thrombocytopenia
  • Patient with cold agglutinin-related AHAI (C3d-positive ADT alone with identification of cold agglutinins)
  • Patient with severe disorders of hemostasis:
  • hypofibrinogenemia < 2 g/L,
  • disseminated intravascular coagulation (APTT prolongation>1.2, and PT<50%, and thrombocytopenia<100 G/L, and D-Dimer >500 µg/L)
  • hemophilia
  • Patient whose clinical condition requires hospitalization in an intensive care unit
  • Patient who has already participated in the study
  • Patient not affiliated to national health insurance
  • Patient under legal protection (curatorship, guardianship)
  • Patient subject to a measure of legal protection
  • Pregnant, parturient or breastfeeding women
  • Patient with physiological capacity to procreate (having had her first menstrual period and not menopausal and not presenting permanent sterility (hysterectomy, bilateral salpingectomy, bilateral oophorectomy)) and unable to have effective contraception (i.e., provided by an estrogen-progestin oral contraceptive or progestogen, a contraceptive implant, an intrauterine device or a tubal ligation)
  • Patient of legal age who is unable to provide consent

Study description and what participation involves

The registry record has no detailed description beyond the summary above.

AI summaryWhat participation may involve, in plain languageShow ▾Hide ▴

AI-written from the registry record, not the study's own wording. May contain errors or omissions. Check the registry text on this page and the original record ↗ before acting on it.

Participants are randomly assigned to two groups: both receive prophylactic heparin while hospitalized; the intervention group then continues oral apixaban for a total of 12 weeks while the standard group does not receive continued prophylactic anticoagulation after hospital discharge. Study visits include blood tests for blood count and hemolysis markers (CBC, reticulocytes, haptoglobin, LDH, bilirubin) and clinical follow-up; investigators will monitor for blood clots for up to 24 weeks after randomization. If a blood clot is suspected, diagnostic imaging (leg venous Doppler, chest CT angiography, or lung ventilation/perfusion scan) will be performed. Participation requires study visits and tests and may require temporary changes to interacting medications if applicable.

How the study is structured. Phase II, randomized, open-label (no masking), two parallel groups. Participants are assigned to either continued prophylactic anticoagulation (heparin in hospital then apixaban to total 12 weeks) or to standard care (heparin in hospital then no prolonged anticoagulation). Both groups have blood-based biological assessments related to hemolysis (CBC, reticulocytes, haptoglobin, LDH, bilirubin). The main outcome is clinically confirmed DVT or PE measured through 24 weeks after randomization.

Questions you could ask

These questions are suggestions for a conversation with the study team or your own clinician, not advice.

  • The listed sites are in France. Is any of them reachable for me, and does the study help with travel?
  • Which of the eligibility criteria would need to be checked with tests before I could join?

More on autoimmune hemolytic anemia

Clinical trials49 trials listed for autoimmune hemolytic anemiaEvery trial the registry lists for autoimmune hemolytic anemia, with recruitment status, phase and sites, updated from ClinicalTrials.gov.See all trials →Research updatesWhat changed in autoimmune hemolytic anemia researchLatest monthly update: September 2026. Includes: Negative DAT cases. New research summarized each month in plain language, with links to every source paper.Read the latest update →

Important dates

Study start
Feb 3, 2022
Primary completion
August 2028 (estimated)
Study completion
August 2028 (estimated)
Target enrollment
72 participants (estimated)
Last updated on registry
Dec 22, 2025
Data verified
Oct 10, 2026

Sponsor and research team

The lead sponsor funds and oversees the trial. A pharmaceutical or biotech company sponsor typically means the study is testing that company's drug or device; a hospital, university, or government agency usually indicates investigator-initiated or publicly funded research.

Lead sponsor
Centre Hospitalier Universitaire Dijon

Central study contact

If you're interested in participating, the central contact can answer general questions about the study — including eligibility requirements and how to find a recruiting site near you. Actual eligibility is determined by the site's medical team.

Participating sites (1)

Terms used on this page · explanations by MedicalUpdates.ai

relapse
A condition that improved with treatment and has since returned or worsened.
life expectancy
Some studies require that, in the investigator's judgement, a participant is likely to live long enough to complete the study period. It is a study requirement, not a prediction about any individual.
informed consent
The process of explaining a study, including its risks and what participation involves, so that a person can decide freely whether to take part. Consent is usually documented in writing, and a participant can choose to leave the study later.
contraindication
A reason a particular test or treatment should not be used for a person, for example a metal implant that rules out an MRI scan.
glomerular filtration rate
A blood-test estimate of how well the kidneys are filtering. Lower numbers mean reduced kidney function; many studies set a minimum value.
upper limit of normal
The highest value of a blood test that a laboratory considers normal. Criteria such as '≤ 3 × ULN' mean the result must be no more than three times that value.
Inclusion Criteria
The conditions a person must meet to be considered for the study, for example a confirmed diagnosis, an age range or a test result.
Exclusion Criteria
The conditions that rule a person out even if they meet the inclusion criteria, for example other illnesses, certain medicines or pregnancy.

The study record on this page is reproduced from ClinicalTrials.gov, a database of the U.S. National Library of Medicine, where it was submitted by the study sponsor. MedicalUpdates.ai does not own this content, is not affiliated with or endorsed by ClinicalTrials.gov, NIH, or the U.S. Government, and does not verify the record. Plain-language notes, the glossary and the questions above are added by this site; text in the boxes marked "AI summary" was written by an AI model and may contain errors. Registry records change over time. Check the original record for the current version and discuss eligibility or participation with a qualified healthcare professional.

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