NCT01730131 · National Institute of Neurological Disorders and Stroke (NINDS)
Natural History Study of Progressive Multifocal Leukoencephalopathy (PML)
What this study is about
Background: \- Progressive multifocal leukoencephalopathy (PML) is a severe viral infection of the brain. It is caused by JC virus. Many people have this virus in their bodies all their life, but it is usually kept in check by their immune system. If the immune system does not work right because of a disease or medication, the virus becomes active and can damage cells in the brain.
View original scientific description
Background: \- Progressive multifocal leukoencephalopathy (PML) is a severe viral infection of the brain. It is caused by JC virus. Many people have this virus in their bodies all their life, but it is usually kept in check by their immune system. If the immune system does not work right because of a disease or medication, the virus becomes active and can damage cells in the brain. Not much is known about PML or how it affects the immune system. Researchers want to study people with PML to better understand the natural history of the disease. Objectives: \- To study the natural history of PML. Eligibility: \- Individuals at least 2 years of age who have PML. Design: * Participants will be screened with a physical exam, medical history, and imaging studies. * Participants will have several visits to the National Institutes of Health Clinical Center. There will be an initial visit, monthly visits for the next 6 months, a 12-month visit, and possible visits afterward. * At the initial visit, participants will give blood, urine, and spinal fluid samples. They will also have neurological tests and imaging studies of the brain. * For the next five visits, participants will give blood and urine samples. They will also have neurological tests and imaging studies of the brain. * The 6-month and 12-month visits will repeat the tests from the initial visit. * Other optional procedures include bone marrow samples and skin biopsies. Additional blood tests and imaging studies may be performed. * Treatment will not be provided as part of this study.
Primary outcome measures
To characterize the baseline presentation of patients with JCV infection and/or PML with regard to clinical, radiological, immunological, genetic and viral features.
Time frame: one year following last enrollment
1\. Characterization of distinctive imaging features to differentiate between actively progressing PML, PML-IRIS/inflammatory PML and inactive PML2. Characterization of distinctive clinical features to differentiate between actively progressing PML, PML-IRIS/inflammatory PML, and inactive PML3. Characterization of immune and virological features to differentiate between actively progressing PML, PML-IRIS/inflammatory PML, and inactive PML4. Characterization of immune and virological differences across PML patient populations with different underlying disease, subjects at risk for developing PML, and healthy individuals5. Characterization of genetic susceptibility for development of PML
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Suspected or confirmed PML
- MRI compatible with PML
- Able to participate in the studies and follow-up required by the protocol
- At least 2 years old
Exclusion criteria
- Significant condition, which in the judgment of the principal investigator, would make participation in the diagnostic and research parts of evaluation impossible or risky
- Medical contraindication to MRI (i.e., devices such as a cardiac pacemaker or infusion pump, other metallic implants, metallic foreign objects, body piercings that cannot be removed)
- Inability to provide informed consent, either directly or via legally authorized representative (LAR)
- Unwillingness to consent for collection of biological samples or their cryopreservation Control Patients at Risk for PML INCLUSION CRITERIA:
- Able to participate in the studies and follow-up required by the protocol
- At least 2 years old
- Impaired immune function from any cause and considered at risk for PML (i.e.-history of hematological malignancy, chronic inflammatory disease, history of treatment with immune suppressive or immunomodulatory therapies, primary or acquired immunodeficiency syndromes) EXCLUSION CRITERIA:
- Significant condition, which in the judgment of the principal investigator, would make participation in the diagnostic and research parts of evaluation impossible or risky
- Medical contraindication to MRI (i.e., devices such as a cardiac pacemaker or infusion pump, other metallic implants, metallic foreign objects, body piercings that cannot be removed)
- Inability to provide informed consent, either directly or via legally authorized representative (LAR)
- Unwillingness to consent for collection of biological samples or their cryopreservation Healthy Volunteers INCLUSION CRITERIA:
- Able to participate in the studies and follow-up required by the protocol
- At least 18 years old EXCLUSION CRITERIA:
- Impaired immune function (i.e.-history of hematological malignancy, chronic inflammatory disease, history of treatment with immune suppressive or immunomodulatory therapies, primary or acquired immunodeficiency syndromes)
- Significant condition, which in the judgment of the principal investigator, would make participation in the diagnostic and research parts of evaluation impossible or risky
- Medical contraindication to MRI (i.e., devices such as a cardiac pacemaker or infusion pump, other metallic implants, metallic foreign objects, body piercings that cannot be removed)
- Inability to provide informed consent, either directly or via legally authorized representative (LAR)
- Unwillingness to consent for collection of biological samples or their cryopreservation
Where
- Bethesda, Maryland
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jun 24, 2026 · Source of record for eligibility and locations