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Study of anifrolumab safety in adults with primary antiphospholipid syndrome (APS)

Verified siteInvestigationalNo placebo
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What is this trial about?

A plain-language summary of the goals, design and what participants do

This study focuses on patients with Primary Antiphospholipid Syndrome (APS), an autoimmune disorder that causes blood clots to form in blood vessels. The research evaluates a medication called anifrolumab (also known as MEDI-546), which is given as a solution for injection under the skin (subcutaneous injection).

The purpose of this research is to assess the safety and how well patients tolerate anifrolumab when used to treat APS. The study is designed as an open-label trial, which means all participants will receive the active medication. The treatment period lasts for 52 weeks, during which participants will receive regular doses of anifrolumab through subcutaneous injections.

Throughout the study, doctors will monitor participants for any side effects, with special attention to certain medical conditions such as infections, shingles (herpes zoster), influenza, and allergic reactions (anaphylaxis). They will also track various health measurements including blood tests to check for specific antibodies and proteins that are important in APS, as well as assess how the treatment affects participants' quality of life and daily activities.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial medical assessment

    A chest x-ray or lung CT scan will be performed to check for any infections or abnormalities

    A SARs-CoV-2 test (COVID-19) will be conducted

    Female patients will need to provide documentation of a normal Pap smear from the past 2 years

    Basic health measurements including weight check (must be at least 40 kg)

    Pregnancy test for females who can become pregnant

  2. Step 2

    Treatment phase begins

    Anifrolumab will be administered through subcutaneous injection (under the skin)

    Regular monitoring for side effects and health changes will begin

    Treatment continues for 52 weeks (1 year)

  3. Step 3

    Regular health assessments

    Health checks at weeks 4, 12, 24, 36, 48, and 52

    Blood tests to monitor various health markers

    Assessment of quality of life using standard questionnaires

    Physical examinations to check for any changes in symptoms

  4. Step 4

    Safety monitoring

    Continuous monitoring for side effects, particularly:

    Infections

    Herpes zoster (shingles)

    Influenza (flu)

    Any allergic reactions

  5. Step 5

    Final assessment

    Complete evaluation of health status at week 52

    Final blood tests and physical examination

    Assessment of treatment effectiveness

    Review of any side effects experienced during the study

Who can join the trial?

14 criteria

  • Must provide written informed consent before any study procedures begin
  • Must be between 18 and 70 years old at screening
  • Must weigh at least 40.0 kg at screening
  • Must have a chest X-ray or lung CT scan showing no active infections, tuberculosis, cancer, or significant abnormalities within 12 weeks before enrollment
  • Must test negative for SARS-CoV-2 (COVID-19) at screening
  • Must be diagnosed with primary Antiphospholipid Syndrome (APS) according to specific medical criteria, excluding pregnancy-related cases
  • Female participants with a cervix must have had a normal Pap smear within 2 years before the study start
  • Women who can become pregnant must:
    • Have a negative pregnancy test at screening
    • Agree to use highly effective birth control throughout the study and for 20 weeks after
    • Male participants must:
      • Use condoms during the study and for 20 weeks after if sexually active with women who can become pregnant
      • Not donate sperm during the study and for 20 weeks after
      • Regarding tuberculosis (TB), participants must:
        • Have no history of active TB
        • Show no current TB symptoms
        • Have negative or appropriately treated TB test results

Who cannot join the trial?

13 criteria

  • Current or history of any blood clotting disorders other than Primary Antiphospholipid Syndrome
  • Known allergic reactions to Anifrolumab or similar medications
  • Current pregnancy or breastfeeding
  • Active or chronic infections, including hepatitis B, hepatitis C, HIV, or tuberculosis
  • History of cancer within the past 5 years (except for successfully treated skin cancer)
  • Severe kidney or liver disease
  • Major surgery within 8 weeks before starting the study
  • Participation in another clinical trial within the past 30 days
  • Substance abuse or alcohol dependency within the past 6 months
  • Mental health conditions that could interfere with study participation
  • Use of prohibited medications, including immunosuppressive drugs (medicines that lower the body's ability to fight infections)
  • Severe, uncontrolled high blood pressure or heart disease
  • Any condition that, in the opinion of the study doctor, makes participation unsafe
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Investigated drugs

Anifrolumab is a medication that works by blocking a protein called type I interferon receptor. It is designed to reduce inflammation in the body. This medication is currently being studied for treating Primary Antiphospholipid Syndrome (APS), an autoimmune disorder where the body's immune system mistakenly creates antibodies that make the blood more likely to clot. The medication is given through an intravenous infusion (through a vein).

What is already known about the treatment

Anifrolumab – A monoclonal antibody medication administered through intravenous infusion that works by blocking type I interferon receptors in the immune system. This drug is currently being investigated in clinical trials for the treatment of Primary Antiphospholipid Syndrome (APS), building upon its established use in systemic lupus erythematosus. Anifrolumab belongs to the class of biological response modifiers and functions by reducing the overactive immune response associated with autoimmune conditions by specifically targeting the type I interferon signaling pathway. The medication is being studied to evaluate its safety and effectiveness in managing APS, a disorder characterized by blood clots and pregnancy complications due to the presence of antiphospholipid antibodies.

Investigated diseases

Primary Antiphospholipid Syndrome (APS) - An autoimmune disorder where the body's immune system mistakenly produces antibodies that attack certain proteins in the blood. These antibodies can cause blood to clot more easily than normal in both arteries and veins. The condition can affect various organs and tissues in the body, leading to complications such as blood clots in the legs, lungs, or other parts of the body. The disease can also affect pregnant women, causing pregnancy complications. Some patients may develop skin changes, including a lace-like purple rash or skin ulcers.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IITrial ID2025-520918-64-00Protocol codeD3461C00035Estimated enrolment20 patientsSponsorNational And Kapodistrian University Of Athens

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