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Study Using PET Imaging to See How [89Zr]Zr-DFO-CIT-013 Spreads in Patients with Inflammatory Mediated Immune Diseases

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 involves patients with inflammatory mediated immune diseases, which are conditions where the body's immune system causes long-lasting inflammation that can damage tissues and organs. The study will specifically include people with rheumatoid arthritis, a disease that causes painful swelling in the joints, and hidradenitis suppurativa, a skin condition that causes painful lumps and tunnels under the skin. The treatment being studied is [89Zr]Zr-DFO-CIT-013, which is a radioactive substance that can be seen on special imaging scans. This substance is given as an infusion into a vein.

The purpose of this study is to see where the radiolabeled substance travels and collects in the body of patients with these inflammatory immune diseases. During the study, participants will receive a single dose of [89Zr]Zr-DFO-CIT-013 through an intravenous injection, which means it will be given directly into a vein. After receiving the treatment, participants will undergo PET-CT imaging scans, which are special types of scans that combine two imaging methods to create detailed pictures of the inside of the body. The main scan will be done 24 hours after the treatment is given.

The study will also monitor participants for any unwanted effects that may occur after receiving the treatment and will measure the levels of the substance in the blood over time. The imaging scans will show how much of the radioactive substance collects in different organs and body systems, and doctors will compare these patterns between patients with different types of inflammatory immune diseases. The maximum amount of the treatment that can be given is 20 milligrams, and the treatment period lasts for one day.

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

    Receiving the study medication

    You will receive a single dose of the study medication called [89Zr]Zr-DFO-CIT-013.

    This medication is a radiolabeled substance, which means it contains a small amount of radioactive material that allows doctors to track where it goes in your body.

    The medication will be given to you through intravenous injection, which means it will be injected directly into a vein.

    The medication is prepared as a concentrate for solution for infusion, which will be diluted before being given to you.

  2. Step 2

    First imaging scan

    Approximately 24 hours after receiving the study medication, you will undergo a PET-CT imaging scan.

    This scan will be performed on Day 2 of the study.

    A PET-CT scan is a type of medical imaging that combines two scanning technologies to create detailed pictures of the inside of your body.

    The scan will show where the radiolabeled medication has traveled in your body and which organs or tissues have absorbed it.

    This is a whole body scan, meaning images will be taken of your entire body.

  3. Step 3

    Monitoring for side effects

    Throughout the study period, you will be monitored for any side effects or unwanted reactions to the study medication.

    This monitoring will include checking for any treatment-emergent adverse events, which are any health problems that occur after receiving the medication.

    Your blood may be tested to check for anti-drug antibodies, which are substances your immune system might produce in response to the medication.

    The frequency and severity of any side effects will be recorded.

  4. Step 4

    Blood sample collection

    Blood samples will be collected from you at various times during the study.

    These samples will be used to measure pharmacokinetic levels, which show how the medication moves through your body over time.

    This includes measuring how much of the medication is in your blood at different time points.

  5. Step 5

    Contraception requirements for male participants

    If you are a male participant with a female partner who can become pregnant, you must use an adequate form of contraception during the study.

    This contraception requirement begins before you enter the study and continues for 6 months after receiving the study medication.

    You must also refrain from donating sperm during this same time period.

Who can join the trial?

10 criteria

  • You must be between 60 and 85 years of age
  • You must be willing and able to provide written informed consent, which means you agree in writing to take part in the study after understanding what it involves
  • If you are a woman, you must be of non-childbearing potential, which means you are unable to become pregnant, usually due to menopause or surgery
  • If you are a man with a female partner who can become pregnant, you must use an adequate form of contraception, which means reliable birth control methods, starting before the study and continuing for 6 months after receiving the study medication
  • If you are a man, you must not donate sperm before the study and for 6 months after receiving the study medication
  • If you have rheumatoid arthritis, which is a condition causing joint inflammation and pain, you must have been diagnosed according to specific medical criteria at least 6 months before screening, with diagnosis confirmed by your medical records
  • If you have active rheumatoid arthritis, you must have a DAS28-CRP score of 4.2 or higher, which is a measurement of disease activity, and have at least 1 swollen joint and at least 1 tender joint at the time of screening
  • If you have rheumatoid arthritis in remission, which means your disease is controlled, you must have a DAS28-CRP score of 2.6 or lower and have no swollen or tender joints at the time of screening
  • If you have hidradenitis suppurativa, which is a skin condition causing painful lumps under the skin, you must have had this condition for at least 6 months, confirmed by your medical records
  • If you have hidradenitis suppurativa, you must have an IHS4 score of 7 or higher, which is a measurement of disease severity, and have at least 1 draining tunnel, which is a connected passage under the skin that releases fluid, at the time of screening

Who cannot join the trial?

1 criterion

  • No specific exclusion criteria (reasons why you cannot participate) have been provided for this clinical trial at this time
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Investigated drugs

CIT-013 is an investigational medication being studied for patients with inflammatory mediated immune diseases. In this trial, it will be labeled with a radioactive tracer so that researchers can track where it goes in the body using special imaging scans called PET scans. This helps doctors understand how the medication distributes throughout the body in patients with these conditions.

What is already known about the treatment

CIT-013 – CIT-013 is an investigational medication currently being studied in clinical trials for the treatment of inflammatory mediated immune diseases, which are conditions where the body's immune system mistakenly attacks its own tissues causing inflammation. The drug is being evaluated using a special imaging technique called PET scanning, where a radiolabeled (radioactive-tagged) version of CIT-013 is administered to patients to track how the medication spreads throughout the body. This research aims to understand where the medication goes in the body and how it might work to treat these immune-related conditions, though its exact mechanism of action and therapeutic benefits are still under investigation.

Investigated diseases

Inflammatory Mediated Immune Diseases – Inflammatory mediated immune diseases are a group of conditions where the body's immune system mistakenly attacks its own healthy tissues and organs. These diseases occur when the immune system becomes overactive and produces an excessive inflammatory response without a clear external threat. The inflammation can affect various parts of the body, including joints, skin, digestive system, blood vessels, and other organs. Symptoms vary widely depending on which organs are affected but commonly include pain, swelling, redness, fatigue, and reduced function of the affected areas. The course of these diseases is often chronic, meaning they persist over long periods and may have periods of increased symptoms followed by times of improvement. The underlying cause involves complex interactions between genetic factors and environmental triggers that lead to the immune system malfunction.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IITrial ID2025-522189-60-00Protocol codeCityviewEstimated enrolment12 patientsSponsorCitryll B.V.

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