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Study on the Safety and Effectiveness of CGT9486 for Patients with Nonadvanced Systemic Mastocytosis

Fast replyInvestigationalNo 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 a condition known as Systemic Mastocytosis, specifically its nonadvanced forms, which include Indolent Systemic Mastocytosis and Smoldering Systemic Mastocytosis. These are conditions where certain immune cells, called mast cells, build up in the body and can cause various symptoms. The study is testing a treatment called CGT9486, also known as bezuclastinib, which is a type of medication that targets specific proteins involved in the disease process. This medication is taken orally in the form of a tablet.

The purpose of the study is to evaluate the safety and effectiveness of CGT9486 compared to a placebo in patients with nonadvanced systemic mastocytosis. The study is divided into three parts. In the first part, the goal is to determine the best dose of bezuclastinib for patients. The second part aims to assess how well the medication works at the chosen dose compared to a placebo. The third part focuses on understanding the safety and how well patients tolerate the medication.

Participants in the study will take the medication or placebo for a period of time, and their health will be monitored to see how they respond to the treatment. The study will look at changes in symptoms and any side effects that may occur. The overall duration of the study is planned to last until 2026, with the aim of gathering comprehensive data on the treatment's impact on the 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, you will be assigned to one of the study groups. This assignment is random, meaning it is like flipping a coin to decide which group you will be in. You will not know which group you are in, and neither will the study team. This is called a double-blind study.

  2. Step 2

    Receiving medication

    You will receive either the study medication called CGT9486 or a placebo. A placebo looks like the medication but does not contain the active ingredient. The medication is in the form of a tablet that you will take by mouth.

  3. Step 3

    Medication schedule

    The exact dosage and frequency of the medication will be determined during the study. You will be informed about how often and how much of the medication you need to take. It is important to follow the instructions given to you by the study team.

  4. Step 4

    Monitoring and assessments

    Throughout the study, you will have regular check-ups to monitor your health and any changes in your condition. This includes safety assessments to check for any side effects, as well as tests to measure how the medication is working.

  5. Step 5

    End of study participation

    Your participation in the study will last until the end of the study period, which is estimated to be in November 2026. At the end of your participation, you will have a final assessment to review your health and any effects of the medication.

Who can join the trial?

8 criteria

  • Must be diagnosed with one of the following types of **systemic mastocytosis** (a condition where certain cells build up in the body):
    • **Indolent systemic mastocytosis (ISM)**
    • **Smoldering systemic mastocytosis (SSM)**
    • **Bone marrow mastocytosis (BMM)**
    • Must have **moderate-to-severe symptoms** based on a specific questionnaire about the disease and be on a stable treatment plan with at least two medications that help control symptoms for at least 14 days.
    • Must have an **Eastern Cooperative Oncology Group (ECOG) Performance Status** of 0 to 2, which means the person is fully active or has some symptoms but can still take care of themselves.
    • Must meet other specific criteria defined in the study protocol.
    • Both **male and female** participants are eligible.
    • Participants from **vulnerable populations** are eligible.

Who cannot join the trial?

10 criteria

  • Patients with any other serious health condition that might interfere with the study.
  • Patients who are pregnant or breastfeeding.
  • Patients who have participated in another clinical trial within the last 30 days.
  • Patients who have a known allergy to the study medication or its ingredients.
  • Patients who are unable to take oral medication.
  • Patients with a history of drug or alcohol abuse within the past year.
  • Patients with a history of certain heart conditions.
  • Patients with uncontrolled high blood pressure.
  • Patients with active infections that require treatment.
  • Patients with a history of cancer, except for certain types of skin cancer.
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Investigated drugs

Bezuclastinib is a medication being studied for its potential to help people with a condition called NonAdvanced Systemic Mastocytosis. This condition involves an abnormal increase in certain cells in the body, which can cause a variety of symptoms. Bezuclastinib is taken by mouth and is being tested to find out the best dose that can be safely used. The study also aims to see how well it works in reducing the symptoms of this condition and to understand any side effects it might have. The goal is to see if bezuclastinib can improve the quality of life for people with this condition by managing their symptoms effectively.

What is already known about the treatment

Bezuclastinib – Bezuclastinib is an oral medication currently being studied in a clinical trial for its safety and effectiveness in treating NonAdvanced Systemic Mastocytosis, a condition where certain immune cells build up in the body. This medication is taken by mouth, and the trial aims to find the best dose and compare its effects to a placebo. Bezuclastinib works by targeting specific molecules in the body to help reduce the symptoms of the disease. It is classified as a targeted therapy, which means it aims to interfere with specific pathways involved in the disease process.

Investigated diseases

Nonadvanced Systemic Mastocytosis – Nonadvanced Systemic Mastocytosis is a condition characterized by the accumulation of mast cells in various tissues, which can lead to a range of symptoms. These mast cells release chemicals like histamine, causing symptoms such as skin rashes, itching, and flushing. Over time, individuals may experience gastrointestinal issues, such as diarrhea and abdominal pain, due to the involvement of the digestive tract. The disease can also affect the bones, leading to bone pain or osteoporosis. Symptoms can vary widely among individuals and may fluctuate in intensity. The progression of the disease is generally slow, with symptoms often managed through lifestyle adjustments.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IITrial ID2022-501427-24-00Protocol codeCGT9486-21-202Estimated enrolment224 patientsSponsorCogent Biosciences Inc.

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On this site, “treatment” means an investigational medicine being studied in a clinical trial. Its safety and efficacy for the use being studied have not yet been confirmed, some participants may receive a placebo or a comparator medicine, and taking part does not guarantee any health benefit. The decision to take part is made by the doctor at the research site. This site is for information only and does not replace medical advice.

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