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Study on RZ358 for Treating Congenital Hyperinsulinism in Patients

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 , which causes low blood sugar levels, or , due to excessive insulin production. The trial will evaluate a treatment called , which is a type of medication known as a . This medication is designed to target and block the insulin receptor, potentially helping to manage blood sugar levels in patients with this condition. The study will also include a group for comparison.

The purpose of the study is to assess how effective and safe is in treating patients with . Participants in the study will receive the treatment through an , which means the medication will be administered directly into a vein. The study will last for a period of 24 weeks, during which the frequency of events will be monitored. This will help determine if can reduce the number of low blood sugar episodes experienced by patients.

Throughout the study, participants will be closely monitored for any side effects or changes in their health. This will include regular check-ups, blood tests, and other assessments to ensure the safety and well-being of all participants. The study aims to provide valuable information on the potential benefits of for individuals with and contribute to the development of new treatment options for this condition.

The research process

The trial runs in 7 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 asked to provide written informed consent. This means you agree to participate after understanding the study's purpose and procedures.

    If applicable, you may also need to provide assent, which is a form of agreement for participants who are minors.

  2. Step 2

    Initial assessment

    You will undergo an initial assessment to confirm your eligibility. This includes verifying your age, which should be between 3 months and 45 years.

    A clinical diagnosis of congenital hyperinsulinism will be confirmed, and your previous treatment history will be reviewed to ensure you have not achieved adequate glycemic control with standard therapies.

  3. Step 3

    Screening tests

    Screening tests will be conducted, including monitoring your blood sugar levels to confirm frequent hypoglycemia events.

    A hepatic ultrasound will be performed to check for any significant liver issues.

  4. Step 4

    Pregnancy test and contraception

    If you are a female of childbearing potential, a pregnancy test will be required before starting the study.

    You will need to agree to use effective contraceptive methods during the study and for at least 3 months after the last dose of the study drug.

  5. Step 5

    Treatment phase

    You will be randomly assigned to receive either the study drug, RZ358, or a placebo. This is a double-blind study, meaning neither you nor the researchers will know which you are receiving.

    The medication will be administered as an intravenous infusion, which means it will be given directly into your vein. The treatment will last for 24 weeks.

  6. Step 6

    Monitoring and assessments

    Throughout the study, your blood sugar levels will be regularly monitored using self-monitored blood glucose (SMBG) and continuous glucose monitoring (CGM) devices.

    You will also undergo regular safety assessments, including laboratory tests, physical exams, and possibly additional ultrasounds.

  7. Step 7

    End of treatment

    After 24 weeks, the treatment phase will conclude. You will have a final assessment to evaluate the effects of the treatment on your blood sugar levels and overall health.

    You may be asked to continue monitoring your blood sugar levels for a short period after the study ends.

Who can join the trial?

9 criteria

  • Provide written informed consent, and if applicable, assent, before any study-specific procedures are performed.
  • Be aged at least 3 months (corrected for gestational age for children under 9 months) and no older than 45 years at the time of screening.
  • Have a confirmed clinical diagnosis of congenital hyperinsulinism (HI), with or without a known genetic cause identified through testing.
  • Have not achieved adequate blood sugar control despite trying standard medical treatments available locally, such as diazoxide and somatostatin analogs (SSAs), as judged by the study doctor.
  • Experience at least 3 episodes of hypoglycemia (low blood sugar, less than 70 mg/dL or 3.9 mmol/L) per week, as measured by self-monitoring or as evaluated by the study doctor. Additionally, have an average daily time with low blood sugar of at least 8% during the monitored screening period.
  • Have a liver ultrasound at screening that shows no significant issues, such as large or obstructive gallstones or signs of a liver condition called peliosis hepatitis, as judged by the study doctor.
  • For female participants who can become pregnant, have a negative pregnancy test within 7 days before starting the study treatment.
  • For female participants who can become pregnant, agree to use highly effective birth control methods to prevent pregnancy during the study and for at least 3 months after the last dose of the study drug. If using hormonal birth control, it is recommended to also use a second method, like a barrier method (e.g., condoms).
  • For sexually active male participants, agree to use contraceptive measures, such as condoms, during the study and for at least 3 months after the last dose of the study drug. Additionally, agree not to donate sperm during this period.

Who cannot join the trial?

10 criteria

  • Patients with other serious health conditions that might interfere with the study.
  • Patients who are pregnant or breastfeeding.
  • Patients who have participated in another clinical trial recently.
  • Patients who have allergies to the study medication or its ingredients.
  • Patients who are unable to follow the study procedures or instructions.
  • Patients with a history of drug or alcohol abuse.
  • Patients with certain heart conditions.
  • Patients with severe kidney or liver problems.
  • Patients who are taking medications that might interfere with the study drug.
  • Patients with a history of certain mental health conditions.
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Investigated drugs

RZ358 is a medication being studied for its potential to help people with congenital hyperinsulinism, a condition where the body produces too much insulin, leading to low blood sugar levels. This medication is designed to help manage blood sugar levels by reducing the effects of excess insulin in the body. The goal of using RZ358 in this trial is to see if it can help prevent episodes of low blood sugar, making it easier for patients to maintain stable blood sugar levels over a period of 24 weeks.

What is already known about the treatment

RZ358 – RZ358 is administered intravenously, meaning it is given directly into a vein through an injection. It is currently being studied in clinical trials and is not yet widely available in medical practice. The main use of RZ358 is to treat hypoglycemia, which is low blood sugar, in patients with congenital hyperinsulinism, a condition where the body produces too much insulin. At the molecular level, RZ358 works by blocking the effects of insulin on its receptor, helping to prevent dangerously low blood sugar levels. It is classified as an anti-hypoglycemic agent, which means it helps to prevent or treat low blood sugar.

Investigated diseases

Hypoglycemia associated with congenital hyperinsulinism – This condition is characterized by low blood sugar levels due to excessive insulin production from the pancreas. It is a genetic disorder where the insulin-producing cells in the pancreas release too much insulin, even when blood sugar levels are low. The disease often presents in infancy or early childhood, leading to symptoms such as irritability, lethargy, and seizures due to low blood sugar. Over time, if not managed, it can cause developmental delays and neurological issues. The frequency and severity of hypoglycemic episodes can vary, and they may occur spontaneously or be triggered by fasting or illness. The condition requires careful monitoring of blood sugar levels to prevent episodes of hypoglycemia.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2023-503240-13-00Protocol codeRZ358-301Estimated enrolment84 patientsSponsorRezolute 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.

This service is not affiliated with the European Commission, the EMA, or the official CTIS system. Most information comes from publicly available international clinical-trial registries, supplemented by data from academic sites, national regulators and commercial sponsors. On this site, “treatment” and “therapy” mean a medicine being tested in a clinical trial. Its safety and effectiveness in the use being studied are not yet confirmed, some participants may receive a placebo or a comparator, and taking part does not guarantee a health benefit. The doctor at the research site decides who can take part. This site provides information, not medical advice. Certain content and visual elements on this website have been generated or enhanced using artificial intelligence (AI).