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Study on the Safety of INF904 for Patients with Moderate to Severe Chronic Spontaneous Urticaria or Hidradenitis Suppurativa

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 clinical trial is focused on studying two conditions: Chronic Spontaneous Urticaria (CSU) and Hidradenitis Suppurativa (HS). These are conditions where the body experiences persistent hives or painful lumps under the skin, respectively. The study will use a treatment called INF904, which is taken as a soft capsule by mouth. INF904 is a type of medication known as a C5aR1 inhibitor, which is designed to help manage these conditions by targeting specific pathways in the body that contribute to inflammation and symptoms.

The purpose of the study is to determine the safety of INF904 when taken in multiple doses by people with moderate to severe CSU or HS. Participants will take the medication over a period of time, and researchers will monitor them to see how their bodies respond to the treatment. This includes looking at how the medication is absorbed and processed in the body, which is known as pharmacokinetics. The study will also track any side effects or adverse events that occur during the trial.

Participants in the study will be asked to take the medication as directed and attend regular check-ups with the research team. These visits will help ensure that the treatment is working as intended and that any potential side effects are managed. The study aims to provide valuable information on the safety and effectiveness of INF904 for people living with CSU or HS, potentially leading to better treatment options in the future.

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 assessment

    Upon joining the study, an initial assessment is conducted to confirm eligibility. This includes reviewing medical history and current health status.

    For those with chronic spontaneous urticaria (CSU), a diagnosis must have been present for at least 6 months, with symptoms inadequately controlled by second-generation H1-antihistamines.

    For those with hidradenitis suppurativa (HS), a diagnosis must have been present for at least 6 months, with a history of inadequate response to oral antibiotics.

  2. Step 2

    Medication administration

    Participants receive the study medication, INF904, which is an oral capsule taken by mouth.

    The medication is administered in multiple doses over the course of the study. The specific dosage and frequency are determined by the study protocol.

  3. Step 3

    Monitoring and evaluation

    Regular monitoring is conducted to evaluate the safety and effects of the medication. This includes tracking any side effects or adverse events.

    Participants may be required to complete a daily symptom diary to record their experiences and any changes in symptoms.

  4. Step 4

    Follow-up visits

    Scheduled follow-up visits are conducted to assess the participant's health and response to the medication.

    These visits may include physical examinations, blood tests, and other assessments as outlined in the study protocol.

  5. Step 5

    Study completion

    Upon completion of the study period, a final evaluation is conducted to gather comprehensive data on the participant's response to the treatment.

    The study aims to determine the safety and pharmacokinetics of INF904 in individuals with moderate to severe CSU or HS.

Who can join the trial?

12 criteria

  • Must be able to give signed informed consent, which means agreeing to participate after understanding the study details.
  • Must be 18 years or older at the time of signing the informed consent.
  • For Hidradenitis Suppurativa (HS):
    • Must have had an inadequate response to at least 3 months (90 days) of oral antibiotics for HS, or cannot take these antibiotics due to intolerance or other medical reasons.
    • Must have moderate or severe HS, classified as Hurley Stage II or III, with at least 5 active nodules (AN count) at screening and baseline. The condition should affect at least 2 different body areas.
    • Must have a diagnosis of HS based on medical history and physical examination for at least 6 months before the baseline visit, with verifiable medical records.
    • Must have stable HS for at least 2 months before screening, as confirmed by the investigator through interviews and medical history review.
    • For Chronic Spontaneous Urticaria (CSU):
      • Must be diagnosed with moderate to severe CSU that is not well controlled by second-generation H1-antihistamines at the time of randomization. This includes:
        • Having itch and hives for 6 or more consecutive weeks before screening, despite using non-sedating H1-antihistamines as per local guidelines.
        • Having a UAS7 score (a measure of urticaria activity) of 16 or more and a UCT7 score (a measure of urticaria control) of less than 12 during the 7 days before randomization (Day 1).
        • Being a non-responder to Anti-IgE therapy, which means having previously received at least 300 mg of this therapy every 4 weeks for at least 4 months (minimum of 4 injections) without adequate response, leading to discontinuation as confirmed by the investigator.
        • Must have had a CSU diagnosis for 6 months or more.
        • Must be capable of completing a daily symptom diary for the study duration and attending scheduled study visits.
        • Must not have any missing diary entries in the 7 days before randomization (Day 1).

Who cannot join the trial?

4 criteria

  • Patients who do not have **Moderate to Severe Chronic Spontaneous Urticaria (CSU)** or **Moderate to Severe Hidradenitis Suppurativa (HS)** cannot participate. **Chronic Spontaneous Urticaria (CSU)** is a condition where hives appear on the skin without a known cause. **Hidradenitis Suppurativa (HS)** is a skin condition that causes small, painful lumps under the skin.
  • Patients who are not within the specified age range for the study cannot participate. The study includes certain age groups, so patients must fall within these age categories.
  • Patients who do not meet the gender requirements for the study cannot participate. The study is open to both male and female participants.
  • Patients who are considered part of a vulnerable population may not be eligible. A vulnerable population includes groups who may need special protection or care.
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Investigated drugs

INF904 is an oral medication being studied for its safety and how it behaves in the body. It is designed to block a specific receptor called C5aR1. This receptor is involved in the body's immune response, and by blocking it, INF904 may help reduce symptoms in people with certain skin conditions. The trial is looking at how well this medication works for people with moderate to severe chronic spontaneous urticaria, which is a type of hives, or hidradenitis suppurativa, a condition that causes painful lumps under the skin.

What is already known about the treatment

INF904 – This medication is administered orally and is currently being studied in a Phase 2a clinical trial. It is being evaluated for its safety and pharmacokinetics in individuals with moderate to severe chronic spontaneous urticaria or hidradenitis suppurativa. INF904 works by inhibiting the C5a receptor 1 (C5aR1), which plays a role in the inflammatory process. It is classified as an oral C5aR1 inhibitor, and its main therapeutic use is aimed at reducing inflammation and symptoms associated with these skin conditions.

Investigated diseases

  • Chronic Spontaneous Urticaria

    This is a skin condition characterized by the sudden appearance of hives, which are red, itchy welts on the skin. These hives can appear anywhere on the body and may change in size and shape. The condition is termed "spontaneous" because the hives occur without an obvious trigger. It is considered chronic when the hives persist for six weeks or longer. The severity can vary, with some individuals experiencing mild symptoms and others having more severe outbreaks. The exact cause is often unknown, but it may involve the immune system.

  • Hidradenitis Suppurativa

    This is a chronic skin condition that causes small, painful lumps to form under the skin. These lumps can break open and cause tunnels under the skin, leading to scarring. It typically occurs in areas where skin rubs together, such as the armpits, groin, and under the breasts. The condition can vary in severity, with some people experiencing mild symptoms and others having more extensive skin involvement. The exact cause is not fully understood, but it is thought to involve hair follicles and the immune system. It often starts after puberty and can persist for many years.

Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IITrial ID2024-515615-22-00Protocol codeINF904-P2.1Estimated enrolment75 patientsSponsorInflaRx GmbH

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