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Study on Long-Term Effects of Efanesoctocog Alfa in Preventing Joint Bleeds in Patients with Hemophilia A

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What is this trial about?

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

This clinical trial focuses on studying the long-term effects of a treatment called efanesoctocog alfa in people with hemophilia A. Hemophilia A is a genetic disorder where blood does not clot properly, leading to excessive bleeding. The treatment being tested is a type of medication known as a coagulation factor VIII, which helps the blood to clot and is given as an injection into a vein.

The purpose of this study is to evaluate how well efanesoctocog alfa works in preventing joint bleeds over a long period. Participants in the study will receive regular injections of the medication and will be monitored for any bleeding episodes, particularly in their joints. The study will also look at how the treatment affects joint health over time, including any changes in joint condition and the number of bleeding events.

Participants will be observed for several years to gather information on the effectiveness of the treatment. The study will track the number of bleeding episodes, the amount of medication needed to control bleeding, and any changes in joint health. This information will help to understand the benefits of using efanesoctocog alfa as a regular preventive treatment for people with hemophilia A.

The research process

The trial runs in 6 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Enrollment

    Upon joining the study, the patient will be enrolled after confirming a diagnosis of haemophilia A and providing informed consent. The patient must have been prescribed efanesoctocog alfa for prophylactic treatment within the last six months or at the time of enrollment.

    The patient must have a history of receiving prophylactic treatment for at least 12 months prior to being prescribed efanesoctocog alfa and must provide documented data on previous treatments and bleeding episodes.

  2. Step 2

    Treatment administration

    The patient will receive efanesoctocog alfa as a solution for injection. The medication is administered through an intravenous injection. The specific dosage will be determined based on the patient's needs and the product available, which includes options like 250 IU, 500 IU, 1,000 IU, 2,000 IU, 3,000 IU, and 4,000 IU.

    The frequency and duration of the treatment will be in accordance with the study protocol and the patient's individual treatment plan.

  3. Step 3

    Regular assessments

    The patient will undergo regular assessments to monitor joint health and the effectiveness of the treatment. This includes the Haemophilia Joint Health Score (HJHS) and patient-reported outcomes (PROs).

    For those in the HEAD-US subgroup, an annual ultrasound assessment of the index joints (ankles, elbows, knees) will be conducted.

  4. Step 4

    Documentation

    The patient or their legally designated representative is required to document all bleeding episodes, including any treatments for those episodes. This documentation is crucial for evaluating the treatment's effectiveness.

  5. Step 5

    Follow-up visits

    The patient will attend follow-up visits as per the study schedule. These visits are essential for ongoing monitoring and assessment of the patient's condition and response to treatment.

    Changes in the Haemophilia Joint Health Score (HJHS) will be evaluated at months 12, 24, and 36 to assess joint health over time.

  6. Step 6

    End of study

    The study is estimated to conclude by December 2, 2028. At the end of the study, the patient's overall health and treatment outcomes will be reviewed to determine the long-term effectiveness of efanesoctocog alfa in preventing joint bleeds.

Who can join the trial?

8 criteria

  • Male or female patient with a diagnosis of Haemophilia A.
  • Capable of giving signed informed consent, which means you understand the study and agree to follow its rules.
  • Prescribed with efanesoctocog alfa (a type of medication) for regular treatment within 6 months before joining the study or at the latest during the first visit, following local rules.
  • Must have been on regular treatment with any haemophilia product for at least 12 months before starting efanesoctocog alfa treatment.
  • Have records of treatment and bleeding episodes from the 12 months before starting efanesoctocog alfa treatment until joining the study.
  • Willing to follow the visit schedule and undergo required study assessments, such as HJHS (a joint health score) and PROs (patient-reported outcomes).
  • Willing and able, or have a representative who is willing and able, to document all bleeding episodes and any treatments for those episodes.
  • For those in the HEAD-US subgroup: Agree to have an annual ultrasound check on specific joints (ankles, elbows, knees).

Who cannot join the trial?

8 criteria

  • Patients who do not have Haemophilia A cannot participate. Haemophilia A is a condition where blood does not clot properly, leading to excessive bleeding.
  • Patients who are not within the specified age range cannot participate. The study includes specific age groups, so if you are outside these age ranges, you cannot join.
  • Patients who are not willing to follow the study procedures and requirements cannot participate. This means you must be ready to attend all study visits and follow instructions given by the study team.
  • Patients who have other medical conditions that might interfere with the study cannot participate. This means if you have other health issues that could affect the study results, you may not be eligible.
  • Patients who are currently participating in another clinical trial cannot participate. If you are already part of another study, you cannot join this one at the same time.
  • Patients who have had a recent major surgery or are planning to have surgery during the study period cannot participate. Major surgery can affect your health and the study results.
  • Patients who are pregnant or breastfeeding cannot participate. This is to ensure the safety of both the mother and the baby.
  • Patients who have a history of allergic reactions to the study medication cannot participate. If you have had allergies to similar medications, you may not be eligible.
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Investigated drugs

Efanesoctocog alfa is a medication used in this clinical trial to help people with Hemophilia A. Hemophilia A is a condition where the blood does not clot properly, leading to excessive bleeding, especially in the joints. This medication is given to patients regularly to prevent joint bleeds. It works by replacing a missing protein in the blood that helps with clotting, which can help reduce the number of bleeding episodes and improve joint health over time.

What is already known about the treatment

Efanesoctocog alfa – Efanesoctocog alfa is administered through an injection, typically into a vein, and is used to help manage Haemophilia A. It is currently being studied in clinical trials to assess its long-term effectiveness in preventing joint bleeds in people with this condition. The medication works by replacing a missing protein in the blood that helps with clotting, thereby reducing bleeding episodes. It is classified as a clotting factor replacement therapy.

Investigated diseases

Haemophilia A – Haemophilia A is a genetic disorder caused by a deficiency of clotting factor VIII, which is essential for blood clotting. This condition leads to prolonged bleeding episodes, especially after injuries or surgeries. Individuals with Haemophilia A may experience spontaneous bleeding into joints, muscles, and other tissues, which can cause pain and swelling. Over time, repeated joint bleeds can lead to joint damage and reduced mobility. The severity of the disease varies, with some individuals experiencing frequent bleeding episodes, while others have milder symptoms. It is an inherited condition, typically passed from parents to children through genes.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-517812-31-00Protocol codeSobi.BIVV001-005Estimated enrolment225 patientsSponsorSwedish Orphan Biovitrum AB (publ)

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