A Study of JR-141 in Patients With Mucopolysaccharidosis II (BR21)

July 21, 2025 updated by: JCR Pharmaceuticals Co., Ltd.

Phase II Study of JR-141 in Patients With Mucopolysaccharidosis II

A Phase II open-label, randomized, parallel group, 2 sites (Brazil), designed to evaluate the safety and efficacy of 3 doses of study drug for the treatment of the MPS II.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
18

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Brazil
      • Porto Alegre, Brazil
        • Grupo de Pesquisa Clínica em Genética Médica - HCPA
      • São Paulo, Brazil
        • Igeim - Unifesp

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

1 second and older (Child, Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Males with confirmed diagnosis of MPS II, based on deficient activity of IDS in leucocytes or fibroblasts and/or pathogenic mutations identified in the IDS gene (if enzyme diagnosis was in dried blood spots or plasma, molecular genetics confirmation is mandatory).

  • One of the following age groups:

    1. 0 to 3 years and 11 months old (6 patients, 2 in each dose)
    2. 4 years to 7 years and 11 months old (6 patients, 2 in each dose)
    3. 8 years or older (6 patients, 2 in each dose)
  • Capable of providing written consent by himself, unless the patient is under the age of 18 years at the time of informed consent process, or it is not possible to obtain consent from the patient himself due to his intellectual disabilities associated with MPS II.
  • In the case of a patient who is under the age of 18 years or from whom it is not possible to obtain consent due to his intellectual disabilities associated with MSP II, he may be included if written consent can be provided by legal representative; however written consent should be obtained from the patient himself too, wherever possible.
  • Naïve patients or patients who are receiving enzyme replacement therapy with idursulfase could be included if provided treatment has been stable in the last 6 months and agree to interrupt the treatment at least one week before the first study drug infusion, and agree in suspending this treatment for the duration of the trial.

Exclusion Criteria:

  • Refusal to sign the informed consent form.
  • Unable to perform the study procedures, except for neurocognitive testing.
  • Previous engrafted BMT/HSCT.
  • Surgical or other major medical intervention planned to occur before week 26.
  • Participation in a clinical trial with an investigational drug in the last 12 months.
  • Judged by the investigator or subinvestigator as being unable to undergo lumbar puncture, including those who have difficulties in taking a position for lumber puncture due to joint contracture or those who are likely to experience difficulty breathing during the lumbar puncture process.
  • Judged by the investigator or subinvestigator to be ineligible to participate in the study due to a history of a serious drug allergy or sensitivity.
  • Otherwise judged by the investigator or subinvestigator to be ineligible to participate in the study out of consideration for the subject safety.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: JR-141 2.0 mg/kg/week
Drug: JR-141
IV infusion (lyophilized powder), 1.0 mg/kg/week
Drug: JR-141
IV infusion (lyophilized powder), 2.0 mg/kg/week
Drug: JR-141
IV infusion (lyophilized powder), 4.0 mg/kg/week
Experimental: JR-141 1.0 mg/kg/week
Drug: JR-141
IV infusion (lyophilized powder), 1.0 mg/kg/week
Drug: JR-141
IV infusion (lyophilized powder), 2.0 mg/kg/week
Drug: JR-141
IV infusion (lyophilized powder), 4.0 mg/kg/week
Experimental: JR-141 4.0 mg/kg/week
Drug: JR-141
IV infusion (lyophilized powder), 1.0 mg/kg/week
Drug: JR-141
IV infusion (lyophilized powder), 2.0 mg/kg/week
Drug: JR-141
IV infusion (lyophilized powder), 4.0 mg/kg/week

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Number of participants with Adverse Events
Time Frame: 26 weeks
  • Adverse events
  • Antidrug antibodies
  • Blood pressures in mmHg
  • Heart rate in beats/minute
  • Respiratory rate in breaths/minute
  • Temperature in °C
  • Presence or absence of abnormalities for physical examination
  • Presence or absence of abnormalities for 12-lead electrocardiogram
  • Routine laboratory tests in blood (hematology, liver function, renal function, iron-related levels) and urine (urinalysis)
26 weeks

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Plasma Pharmacokinetic parameter [Maximum Plasma Concentration [Cmax]]
Time Frame: 21 hours after dosing at the first and last infusions
Plasma concentration of JR-141
21 hours after dosing at the first and last infusions
Plasma Pharmacokinetic parameter [Area Under the Curve [AUC]]
Time Frame: 21 hours after dosing at the first and last infusions
Plasma concentration of JR-141
21 hours after dosing at the first and last infusions
Liver and spleen volumes (MRI)
Time Frame: 26 weeks
26 weeks
Left ventricular mass by a standard 2-dimensional Doppler echocardiogram
Time Frame: 26 weeks
26 weeks
Urinary heparan sulfate concentrations
Time Frame: 26 weeks
26 weeks
Urinary dermatan sulfate concentrations
Time Frame: 26 weeks
26 weeks
Serum heparan sulfate concentrations
Time Frame: 26 weeks
26 weeks
Serum dermatan sulfate concentrations
Time Frame: 26 weeks
26 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
JCR Pharmaceuticals Co., Ltd.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
July 26, 2018

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
October 4, 2019

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
October 4, 2019

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
November 17, 2017

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 29, 2017

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
December 2, 2017

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
July 24, 2025

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
July 21, 2025

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
July 1, 2025

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • JR-141-BR21

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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