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Study on Long-Term Safety of Gene Therapy for Pyruvate Kinase Deficiency Using Autologous CD34+ Cells in Adults and Children

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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 rare blood disorder called Pyruvate Kinase Deficiency (PKD). PKD is a condition where the body lacks enough of an enzyme called pyruvate kinase, which is essential for red blood cells to function properly. This can lead to anemia, a condition where the body does not have enough healthy red blood cells. The treatment being studied is a gene therapy product known as Merilen (also referred to by its code name, RP-L301). This treatment involves using the patient's own blood stem cells, which are modified outside the body with a special virus to carry a corrected version of the gene responsible for PKD. These modified cells are then infused back into the patient through a process called intravenous infusion.

The purpose of this study is to evaluate the long-term safety of this gene therapy in both adults and children with PKD. Participants in the study will receive the infusion of their own modified cells and will be monitored over an extended period to assess how well the treatment works and to check for any potential side effects. The study aims to see if the treatment can help reduce the need for blood transfusions and improve anemia symptoms in patients with PKD.

Throughout the study, researchers will keep track of various health indicators, such as overall survival and any changes in the genetic makeup of the blood cells. They will also monitor for any adverse events, including those related to iron overload or the development of any new health conditions. This long-term follow-up is crucial to understanding the potential benefits and risks of the gene therapy for individuals with Pyruvate Kinase Deficiency.

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 visit

    Upon joining the study, you will attend an initial visit. During this visit, your eligibility for the trial will be confirmed based on your previous participation in the parent study RP-L301-0119.

    You will be asked to provide written informed consent to participate in this long-term follow-up study. This consent ensures that you understand the study's purpose and agree to adhere to the study visit schedule and other protocol requirements.

  2. Step 2

    Infusion procedure

    You have already received an infusion of autologous CD34+ cells that were modified with a lentiviral vector carrying the coRPK gene. This step is part of the parent study and is crucial for the follow-up process.

  3. Step 3

    Regular follow-up visits

    You will attend regular follow-up visits to monitor your health and the effects of the gene therapy. These visits are designed to evaluate the long-term safety of the infusion.

    During these visits, blood samples will be taken to assess the persistence of the gene modification in your blood cells and to check for any potential side effects or adverse events.

  4. Step 4

    Monitoring and assessments

    The study will monitor your overall health, including any red blood cell transfusions you may require and any changes in your hemoglobin levels.

    The study will also track any adverse events, such as worsening iron overload or the development of any malignancy, to ensure your safety throughout the trial.

  5. Step 5

    Long-term observation

    The study is designed to continue until July 31, 2038, allowing for long-term observation of the effects of the gene therapy.

    Your participation will help determine the long-term persistence of the gene modification and its impact on reducing anemia and transfusion requirements.

Who can join the trial?

4 criteria

  • The patient was part of the earlier study called RP-L301-0119.
  • The patient received an infusion of their own blood cells, which were enriched with a type of cell called CD34+. These cells were modified outside the body using a special tool called a lentiviral vector to carry a specific gene known as coRPK.
  • The patient is willing and able to follow the schedule for study visits and meet other study requirements.
  • The patient has given written permission to participate in the study, and if needed, has also given assent, which means they agree to take part in the study according to the rules.

Who cannot join the trial?

9 criteria

  • Patients with any other serious medical condition that might affect their participation in the study.
  • Patients who have had a recent infection that could interfere with the study.
  • Patients who are currently pregnant or breastfeeding.
  • Patients who have a history of cancer, except for certain types of skin cancer.
  • Patients who have received another investigational drug or treatment within a certain period before the study.
  • Patients with a known allergy to any component of the study treatment.
  • Patients who have a history of drug or alcohol abuse that might interfere with their ability to follow the study procedures.
  • Patients who have a mental health condition that might affect their ability to participate in the study.
  • Patients who are unable to comply with the study requirements for any reason.
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Investigated drugs

Autologous CD34+ Cells Transduced with a Lentiviral Vector Carrying the Codon Optimized Red Cell Pyruvate Kinase (coRPK) Gene is a type of gene therapy used in this clinical trial. This therapy involves taking some of your own blood cells, specifically CD34+ cells, and modifying them in a laboratory. The modification is done using a special tool called a lentiviral vector, which helps insert a new version of a gene called the codon optimized red cell pyruvate kinase (coRPK) gene into your cells. Once these cells are modified, they are infused back into your body. The goal of this therapy is to help your body produce healthier red blood cells, which can reduce the symptoms of pyruvate kinase deficiency, a condition that affects how your red blood cells function. This therapy is being tested to see if it is safe and effective over a long period of time.

What is already known about the treatment

Autologous CD34+ Cells Transduced with Lentiviral Vector Carrying Codon Optimized Red Cell Pyruvate Kinase Gene – This medication is administered through an infusion, where a patient's own blood cells are modified and then reintroduced into their body. It is currently being studied in clinical trials for its long-term safety and effectiveness in treating pyruvate kinase deficiency, a rare blood disorder. The main therapeutic goal is to reduce the need for blood transfusions and improve anemia by introducing a corrected gene into the patient's blood cells. At the molecular level, the treatment works by using a virus to deliver a healthy version of the gene responsible for producing an important enzyme in red blood cells. This medication falls under the category of gene therapy, which involves altering genes to treat or prevent disease.

Investigated diseases

Pyruvate kinase deficiency – Pyruvate kinase deficiency is a genetic disorder that affects the red blood cells, leading to a condition known as hemolytic anemia. This disease occurs when there is a lack of the enzyme pyruvate kinase, which is crucial for the energy production in red blood cells. As a result, the red blood cells break down too easily, leading to a shortage of these cells in the bloodstream. The progression of the disease can vary, with some individuals experiencing mild symptoms, while others may have severe anemia. Over time, the body may try to compensate for the loss of red blood cells by producing more, but this can lead to complications such as an enlarged spleen. The condition is typically present from birth and can affect individuals throughout their lives.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase ITrial ID2022-501526-38-00Protocol codeRP-L301-0222-LTFUEstimated enrolment5 patientsSponsorRocket Pharmaceuticals Inc.

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