NCT07640984 · JCR Pharmaceuticals Co., Ltd.
A Phase I/II Trial of JR-446 in Mucopolysaccharidosis Type IIIB (MPS IIIB)
What this study is about
This is a global, where both patients and doctors know the treatment given, Phase I/II, interventional trial in participants younger than 6 years of age with Mucopolysaccharidosis Type IIIB (MPS IIIB), designed to assess the safety and how well patients handle the treatment of JR-446, determine its how the drug affects the body effects, and explore its potential to demonstrate early clinical effects on disease-relevant outcomes.
View original scientific description
This is a global, open-label, Phase I/II, interventional trial in participants younger than 6 years of age with Mucopolysaccharidosis Type IIIB (MPS IIIB), designed to assess the safety and tolerability of JR-446, determine its pharmacodynamic effects, and explore its potential to demonstrate early clinical effects on disease-relevant outcomes.
Interventions
DRUG
JR-446
IV infusion
Primary outcome measures
To establish the safety and tolerability of JR-446 in MPS IIIB patients following repeated dose administration
Time frame: Up to 1 year (multiple visits)
Incidence and severity of treatment-emergent adverse events; Incidence and severity of infusion-associated reactions; Incidence of clinically significant changes/abnormalities in safety laboratory tests, vital signs, and electrocardiogram.
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
- Patients with confirmed MPS IIIB with a phenotype of MPS IIIB that is not classified as slowly progressive (i.e., not attenuated).
- A chronological age \<6 years.
- Ability to complete and achieve a Standard score ≥55, using either Bailey Scale of Infant Development-4 (BSID-4) Cognitive domain or Kaufman Assessment Battery for Children-II (KABC-II) Non-Verbal Index, whichever tool is most appropriate for the participant's chronological age.
Exclusion criteria
- Contraindication for lumbar puncture or MRI.
- A participant who has a medical condition or extenuating circumstance that, in the opinion of the principal investigator or sub-investigator, might compromise the participant's ability to comply with protocol requirements, the participant's well-being or safety, or the interpretability of the participant's clinical data.
- A participant who has received any other investigational drug product (including but not limited to, tralesinidase alfa enzyme replacement therapy \[TA-ERT\], Genistein, KINERET \[anakinra\], ambroxol, miglustat) within 4 months (or 5 half-lives, whichever is longer) before the time of providing informed consent.
- A participant who has received gene therapy treatment or hematopoietic stem cell transplantation (HSCT) with successful engraftment.
- Serious drug allergy or hypersensitivity to any components of JR-446 or medications likely prescribed during the trial.
- A participant has a history of bleeding disorder or current use of medications that, in the opinion of the investigator, place them at risk of bleeding following lumbar puncture.
- A patient with recurrent epileptic seizures not adequately controlled with anti-seizure medication, and which, in the clinical judgment of the principal investigator, would preclude safe participation in the trial.
- Serology consistent with human immunodeficiency virus (HIV) exposure or consistent with active hepatitis B (HepB) or hepatitis C (HepC) infection.
- A participant/family, who, in the opinion of the investigator, may not be able to comply with protocol requirements and cooperate fully with the trial assessments, procedures, and scheduling for JR-446 IMP dose administrations.
- Study participants for whom informed consent is unable to be provided by a parent or legal guardian; or when applicable for a study participant who is unable to provide assent with respect to study participation in conjunction with parental or legal guardian consent for participation on study. The above information is not intended to contain all considerations relevant to a patient's potential participation in this clinical trial.
Where
- Oakland, California
- Pittsburgh, Pennsylvania
- Fairfax, Virginia
Collaborators
MEDIPAL HOLDINGS CORPORATION
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 Sep 21, 2026 · Source of record for eligibility and locations