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An Extension Study of JR-141 in Patients With Mucopolysaccharidosis Type II

An Extension Study of JR-141 in Patients With Mucopolysaccharidosis Type II

Status
Active, not recruiting
Phases
Phase 2Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04348136
Enrollment
27
Registered
2020-04-16
Start date
2019-09-01
Completion date
2030-03-31
Last updated
2026-09-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Mucopolysaccharidosis II

Brief summary

Multicenter, open-label, single-group, designed to evaluate the long term efficacy and safety of study drug for the treatment of the MPS II.

Interventions

DRUGJR-141

IV infusion, 2.0 mg/kg/week

Sponsors

JCR Pharmaceuticals Co., Ltd.
Lead SponsorINDUSTRY

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
MALE
Healthy volunteers
No

Inclusion criteria

1. A patient who participated in the preceding Study JR-141-301 and completed the Week 52 visit, and has no safety concerns to enter this study in the opinion of the investigator or subinvestigator. 2. A patient capable of providing written informed consent in person (However, this is not required for patients aged younger than 20 years at the time of consent or patients with intellectual disability associated with MPS II whose willingness cannot be verified.) 3. For patients aged younger than 20 years at the time of consent or patients with intellectual disability associated with MPS II whose willingness cannot be verified, written consent must be obtained from the legally acceptable representative. (Wherever possible, written consent of the patient should be obtained.) 4. Male patient whose partner is of child-bearing potential and agrees to use a medically accepted, highly effective method of contraception.

Exclusion criteria

1. A patient who used any concomitant medication or therapy that could affect study assessments in the opinion of the investigator or subinvestigator. 2. A patient with a history of serious drug allergy or hypersensitivity that precludes participation in this study in the opinion of the investigator or subinvestigator. 3. A patient judged to be ineligible by the investigator or subinvestigator for other reasons.

Design outcomes

Primary

MeasureTime frameDescription
Laboratory tests (urinalysis)Week 78, 104, an average of 52 weeks after Week 104, up to approximately 10.6 years
Vital signs (pulse rate)Week 78, 104, an average of 52 weeks after Week 104, up to approximately 10.6 years
Vital signs (body temperature)Week 78, 104, an average of 52 weeks after Week 104, up to approximately 10.6 years
Vital signs (blood pressure)Week 78, 104, an average of 52 weeks after Week 104, up to approximately 10.6 years
12-lead electrocardiogramWeek 78, 104, an average of 52 weeks after Week 104, up to approximately 10.6 yearsThe presence or absence of abnormal findings (if present, specific findings and whether or not they are reported as adverse events)
Antibody tests (anti-JR-141 antibodies)Week 78, 104, an average of 52 weeks after Week 104, up to approximately 10.6 years
IARFrom the start of study (Week 52 of preceding study) up to the end of study, up to approximately 10.6 years
Time course of developmental assessment data (Kyoto Scale of Psychological Development 2001) from initial dosing in the preceding studyWeek 104, an average of 52 weeks after Week 104, up to approximately 10.6 years
Time course of developmental assessment data (Vineland-II) from initial dosing in the preceding studyWeek 104, an average of 52 weeks after Week 104, up to approximately 10.6 years
Time course of developmental assessment data (Bayley-III or KABC-II) from initial dosing in the preceding studyWeek 104, an average of 52 weeks after Week 104, up to approximately 10.6 years
Time course of CSF substrate (HS and DS) concentrations from initial dosing in the preceding studyWeek 104, an average of 52 weeks after Week 104, up to approximately 10.6 years
Time course of serum HS and DS concentrations from initial dosing in the preceding studyWeek 78, 104, an average of 52 weeks after Week 104, up to approximately 10.6 years
Time course of urinary HS concentration from initial dosing in the preceding studyWeek 78, 104, an average of 52 weeks after Week 104, up to approximately 10.6 years
Time course of urinary DS concentration from initial dosing in the preceding studyWeek 78, 104, an average of 52 weeks after Week 104, up to approximately 10.6 years
Time course of uronic acid concentration from initial dosing in the preceding studyWeek 78, 104, an average of 52 weeks after Week 104, up to approximately 10.6 years
Time course of liver volume (assessed by CT or MRI) from initial dosing in the preceding studyWeek 78, 104, an average of 52 weeks after Week 104, up to approximately 10.6 years
Time course of spleen volume (assessed by CT or MRI) from initial dosing in the preceding studyWeek 78, 104, an average of 52 weeks after Week 104, up to approximately 10.6 years
Time course of cardiac function (assessed by echocardiography) from initial dosing in the preceding studyWeek 78, 104, an average of 52 weeks after Week 104, up to approximately 10.6 years
Time course of 6-minute walk test distance from initial dosing in the preceding studyWeek 104, an average of 52 weeks after Week 104, up to approximately 10.6 years
Time course of joint range of motion from initial dosing in the preceding studyWeek 104, an average of 52 weeks after Week 104, up to approximately 10.6 years
Occurrence of adverse reactionsFrom the start of study (Week 52 of preceding study) up to the end of study, up to approximately 10.6 years
Incidence of abnormal vital signsWeek 78, 104, an average of 52 weeks after Week 104, up to approximately 10.6 yearsLaboratory tests (hematology)
Occurrence of adverse eventsFrom the start of study (Week 52 of preceding study) up to the end of study, up to approximately 10.6 years

Countries

Japan

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Sep 4, 2026