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Study on the Safety of Long-Term Use of Deucrictibant for Treating Hereditary Angioedema Attacks in Patients with C1-Inhibitor Deficiency

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What is this trial about?

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

This clinical trial is focused on studying a condition known as Hereditary Angioedema, which is a rare genetic disorder that causes sudden swelling attacks in various parts of the body, including the face, hands, and throat. The study is specifically looking at patients with Hereditary Angioedema due to a deficiency in a protein called C1-Inhibitor, which can be of Type I or Type II. The treatment being tested is an oral medication called Deucrictibant (PHA-022121), which is designed to be taken during an acute attack to help manage the symptoms.

The purpose of this study is to evaluate the safety of long-term use of Deucrictibant for treating these acute attacks, including those affecting the throat, but without causing breathing difficulties. Participants in the study will take the medication as needed during an attack, and their health will be monitored over time to ensure the treatment is safe. The study will also involve a comparison with a placebo, which is a substance with no active medication, to better understand the effects of Deucrictibant.

Throughout the study, participants will be asked to report any side effects they experience, and regular health checks will be conducted, including monitoring vital signs and performing laboratory tests. The study aims to provide valuable information on how well Deucrictibant works in relieving symptoms and improving the quality of life for those with Hereditary Angioedema. This research is important for developing effective treatments for managing this challenging condition.

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

    Joining the study

    Upon joining the study, the participant will begin the trial focused on evaluating the safety of long-term treatment for hereditary angioedema attacks.

    The study involves the use of the medication deucrictibant, which is administered orally in the form of a soft capsule.

  2. Step 2

    Medication administration

    The participant will take deucrictibant as needed for acute angioedema attacks. The medication is taken orally.

    The frequency and dosage will be determined based on the occurrence of attacks and the participant's response to the treatment.

  3. Step 3

    Monitoring and assessments

    Throughout the study, the participant's health will be monitored through various assessments.

    These assessments include checking vital signs, conducting clinical laboratory tests, and performing ECGs (a test that records the electrical activity of the heart).

  4. Step 4

    Evaluation of symptom relief

    The study will evaluate the time it takes for the participant to experience symptom relief after taking the medication.

    This includes measuring the time to onset of symptom relief and the time to substantial symptom relief, using tools like the Patient Global Impression of Change (PGI-C) and the Visual Analog Scale (VAS).

  5. Step 5

    Completion of the study

    The study is expected to continue until June 2027, with ongoing assessments and monitoring.

    The participant will continue to take the medication as needed and attend scheduled assessments until the study concludes.

Who can join the trial?

4 criteria

  • The patient must provide written informed consent. If the patient is under 18 years old, consent must be obtained from a parent or legal guardian, and the patient must also agree in writing.
  • If the patient participated in Study C201, they must have received at least one dose of the study drug. If they participated in Study C306, they must have been part of the study and completed it, with at least two attacks treated, or after the study was closed by the Sponsor.
  • Female patients who can become pregnant must agree to pregnancy testing as specified in the study and must either not engage in heterosexual intercourse or use an acceptable method of birth control from the start of the study until 30 days after the last dose of the study drug.
  • The patient, and if applicable, their parent or caregiver, must be willing and able to follow the study's requirements, as determined by the study doctor.

Who cannot join the trial?

5 criteria

  • Patients who have a different type of hereditary angioedema than Type 1 or 2 C1-Inhibitor deficiency cannot participate.
  • Patients who have breathing difficulties during laryngeal attacks are not eligible.
  • Patients who are not within the specified age range for the study cannot join. The age range includes children, adolescents, and adults.
  • Patients who are not part of the specified clinical trial group are excluded.
  • Patients who are considered part of a vulnerable population, which means they might need special protection or care, are not eligible.
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Investigated drugs

  • PHA-022121

    is an oral medication being studied for its effectiveness in treating sudden swelling attacks in patients with hereditary angioedema, a condition caused by a deficiency in a specific protein. This medication is intended to be used as needed when an attack occurs, helping to manage symptoms quickly and effectively.

  • Deucrictibant

    is another medication involved in the study, focusing on its safety for long-term use in treating acute hereditary angioedema attacks. It is designed to be used on-demand, meaning patients take it when they experience an attack, including those affecting the throat, to help alleviate symptoms without causing breathing difficulties.

What is already known about the treatment

Deucrictibant – This medication is administered orally and is currently being studied in clinical trials for its effectiveness in treating acute attacks of hereditary angioedema (HAE) caused by C1-Inhibitor deficiency, specifically Type 1 and Type 2. It is in the Phase II/III stage of clinical trials, focusing on its safety for long-term, on-demand use. The main therapeutic indication is for managing sudden swelling episodes associated with HAE, including those affecting the larynx. Deucrictibant works by targeting specific pathways involved in the inflammatory response that leads to these swelling attacks. It is classified pharmacologically as a treatment for hereditary angioedema.

Investigated diseases

Hereditary Angioedema – Hereditary angioedema is a rare genetic disorder characterized by recurrent episodes of severe swelling, known as angioedema. This condition is caused by a deficiency or dysfunction of the C1 inhibitor protein, which normally helps regulate inflammation. The swelling can affect various parts of the body, including the extremities, face, intestinal tract, and airway. Attacks can occur spontaneously or be triggered by stress, trauma, or other factors. The swelling episodes can be painful and may last for several days. While the condition is chronic, the frequency and severity of attacks can vary widely among individuals.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IVTrial ID2023-505766-28-00Protocol codePHA022121-C303Estimated enrolment155 patientsSponsorPharvaris Netherlands B.V.

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