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

NCT04348136 | Active Not Recruiting Phase 2

• 1 other identifier: JR-141-302
• Study Type: interventional
• Target: 27
• Locations: 1 country
• Sites: 20

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.

Conditions

Mucopolysaccharidosis II

Outcome Measures

Primary Outcomes (25)

• Occurrence of adverse events

  From the start of study (Week 52 of preceding study) up to the end of study, up to approximately 10.6 years

• Occurrence of adverse reactions

  From 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 signs

  Laboratory tests (hematology)

  Week 78, 104, an average of 52 weeks after Week 104, up to approximately 10.6 years

• Incidence of abnormal vital signs

  Laboratory tests (biochemistry)

  Week 78, 104, an average of 52 weeks after Week 104, up to approximately 10.6 years

• Incidence of abnormal vital signs

  Laboratory tests (iron-related tests)

  Week 78, 104, an average of 52 weeks after Week 104, up to approximately 10.6 years

• 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 electrocardiogram

  The presence or absence of abnormal findings (if present, specific findings and whether or not they are reported as adverse events)

  Week 78, 104, an average of 52 weeks after Week 104, up to approximately 10.6 years

• Antibody tests (anti-JR-141 antibodies)

  Week 78, 104, an average of 52 weeks after Week 104, up to approximately 10.6 years

• IAR

  From 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 study

  Week 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 study

  Week 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 study

  Week 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 study

  Week 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 study

  Week 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 study

  Week 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 study

  Week 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 study

  Week 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 study

  Week 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 study

  Week 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 study

  Week 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 study

  Week 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 study

  Week 104, an average of 52 weeks after Week 104, up to approximately 10.6 years

Study Arms (1)

JR-141

EXPERIMENTAL

Drug: JR-141

Interventions

JR-141 DRUG

IV infusion, 2.0 mg/kg/week

JR-141

Eligibility Criteria

• Sex: male
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• 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.
• 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.)
• 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.)
• Male patient whose partner is of child-bearing potential and agrees to use a medically accepted, highly effective method of contraception.

You may not qualify if:

• A patient who used any concomitant medication or therapy that could affect study assessments in the opinion of the investigator or subinvestigator.
• 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.
• A patient judged to be ineligible by the investigator or subinvestigator for other reasons.

Sponsors & Collaborators

• JCR Pharmaceuticals Co., Ltd.: lead

Study Sites (20)

Fukui Clinical site

Fukui, 910-1193, Japan

Location

Fukuoka Clinical site 2

Fukuoka, 813-0017, Japan

Location

Fukuoka Clinical site

Fukuoka, 830-0011, Japan

Location

Gifu Clinical site

Gifu, 501-1194, Japan

Location

Hiroshima Prefectural Hospital

Hiroshima, 734-8530, Japan

Location

Hokkaido Clinical site

Hokkaido, 063-0005, Japan

Location

Kananagawa Ckinical site

Kanagawa, 232-8555, Japan

Location

Kumamoto Clinical site

Kumamoto, 860-8556, Japan

Location

Okayama Clinical site

Okayama, 701-1192, Japan

Location

Okayama Clinical site 2

Okayama, 710-8602, Japan

Location

Okinawa Clinical site

Okinawa, 903-0215, Japan

Location

Osaka Clinical site 3

Osaka, 534-0021, Japan

Location

Osaka Clinical site 2

Osaka, 545-8586, Japan

Location

Osaka Clinical site

Osaka, 565-0871, Japan

Location

Saitama Clinical site

Saitama, 330-8777, Japan

Location

Shizuoka Clinical site

Shizuoka, 420-8660, Japan

Location

Shizuoka Clinical site 2

Shizuoka, 426-8677, Japan

Location

Tochigi Clinical site

Tochigi, 329-0498, Japan

Location

Tokyo Clinical site

Tokyo, 157-8535, Japan

Location

Tottori Clinical site

Tottori, 683-8504, Japan

Location

MeSH Terms

Conditions

Mucopolysaccharidosis II

Condition Hierarchy (Ancestors)

X-Linked Intellectual Disability; Intellectual Disability; Neurobehavioral Manifestations; Neurologic Manifestations; Nervous System Diseases; Genetic Diseases, X-Linked; Genetic Diseases, Inborn; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Heredodegenerative Disorders, Nervous System; Mucopolysaccharidoses; Carbohydrate Metabolism, Inborn Errors; Metabolism, Inborn Errors; Lysosomal Storage Diseases; Mucinoses; Connective Tissue Diseases; Skin and Connective Tissue Diseases; Metabolic Diseases; Nutritional and Metabolic Diseases

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: December 18, 2019
• First Posted: April 16, 2020
• Study Start: September 1, 2019
• Primary Completion (Estimated): March 31, 2030
• Study Completion (Estimated): March 31, 2030
• Last Updated: July 24, 2025

Record last verified: 2025-07

Locations

JP (20)