A Phase III Study of JR-141 in Patients With Mucopolysaccharidosis II (STARLIGHT)

NCT ID: NCT04573023

Last Updated: 2026-01-21

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

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Recruitment Status

ACTIVE_NOT_RECRUITING

Clinical Phase

PHASE3

Total Enrollment

86 participants

Study Classification

INTERVENTIONAL

Study Start Date

2022-02-14

Study Completion Date

2027-10-31

Brief Summary

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A Global Phase III multicenter, randomized, assessor-blinded, active-controlled designed to evaluate safety and efficacy of study drug for the treatment of the MPS II.

Detailed Description

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Conditions

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Mucopolysaccharidosis II

Study Design

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Allocation Method

RANDOMIZED

Intervention Model

PARALLEL

Primary Study Purpose

TREATMENT

Blinding Strategy

SINGLE

Outcome Assessors

Study Groups

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JR-141 2.0 mg/kg/week

Group Type EXPERIMENTAL

JR-141

Intervention Type DRUG

IV infusion, 2.0 mg/kg/week

administered as the standard of care: idursulfase (ELAPRASE®)

standard of care-controlled study

Group Type OTHER

Idursulfase

Intervention Type DRUG

IV infusion

Rescue arm

Group Type OTHER

JR-141 or Idursulfase

Intervention Type DRUG

The subjects who have achieved the pre-specified criteria\* are able to change the drug.

\*If a subject in Idursulfase group shows decline in their neurocognitive outcome, idursulfase can be switched to JR-141.

If a subject in JR-141 group shows decline in their peripheral outcome, JR-141 will be switched to idursulfase.

Interventions

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JR-141

IV infusion, 2.0 mg/kg/week

Intervention Type DRUG

Idursulfase

IV infusion

Intervention Type DRUG

JR-141 or Idursulfase

The subjects who have achieved the pre-specified criteria\* are able to change the drug.

\*If a subject in Idursulfase group shows decline in their neurocognitive outcome, idursulfase can be switched to JR-141.

If a subject in JR-141 group shows decline in their peripheral outcome, JR-141 will be switched to idursulfase.

Intervention Type DRUG

Eligibility Criteria

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Inclusion Criteria

* A patient who voluntarily signs an Institutional Review Board or Independent Ethics Committee-approved written informed consent form. If the patient is aged under 18 years (aged under 16 years in the UK) at the time of enrollment or willingness to participate in the study cannot be confirmed due to MPS II-related intellectual disability, the patient's legally acceptable representative (e.g., his/her parents or guardians) may sign the informed consent on behalf of the patient. Written informed assent should be obtained from the patient, wherever possible.
* Patients with confirmed diagnosis of MPS II
* Naïve patients or patients who are receiving stable enzyme replacement therapy with idursulfase for more than 12 weeks before starting administration of JR-141 or idursulfase for this study.
* Patients or patients whose partners are of child-bearing potential agree to use a medically accepted, highly effective method of contraception being use of condoms from the time of informed consent.

\<Cohort A\>

* Patients aged 36-42 months old at the time of ICF signing: patients must have a standard score measured by the BSID-III of 85 or less at screening.
* Patients aged 43-71 months old at the time of ICF signing: patients must EITHER have (1) A DQ measured by BSID-III of 20 to 85 at screening OR (2) A composite standard score on NVI measured by KABC-II of 85 or less at screening (only who can perform KABC-II)
* Patients aged 30-35 months old at the time of randomization and who are judged as having the severe phenotype by the Expert Board.

\<Cohort B\>

* Patients 6 years of age or older at the time of ICF signing and whose IQ are 70 and higher.
* Enrollment of subjects in Cohort B is contingent on the availability in that country of a validated country-specific version of the test (either WISC-V, WAIS-IV, or T.O.V.A.).
* Attenuated patients with 1 SD deficiency in the omission errors or variability domains of the T.O.V.A..
* Patients or patients whose female partners are of child-bearing potential i.e., fertile, following menarche and until becoming post-menopausal unless permanently sterile, agree to use a medically accepted, highly effective method of contraception, from the time of informed consent. The method of contraception must be used during the study until 90 days for male subjects, and 30 days for female subjects after the final study intervention administration.
* For subjects with hearing impairment requiring hearing aid(s), every effort has been made to encourage compliance with the use of functioning hearing aid(s) before baseline neurocognitive assessments, and parent/legally acceptable representative or subject agrees to encourage wearing them during the study and on neurocognitive testing days.

Exclusion Criteria

* A patient with a history of HSCT with successful engraftment.
* A patient who has received gene therapy treatment at any point.
* A patient who is judged by the principal investigator or sub-investigator as being unable to undergo lumbar puncture, including those who have difficulties in taking position for lumbar puncture due to joint contracture or those who are likely to experience breathing difficulties during the lumbar puncture process.
* A patient who is enrolled in another clinical study that involves clinical investigations or use of any investigational product (drug or device) within 4 months before obtaining informed consent.
* Unable to comply with the protocol as determined by the principal investigator or subinvestigator.
* Judged by the principal investigator or subinvestigator to be ineligible to participate in the study due to a history of serious drug allergy or sensitivity including anesthesia or hypersensitivity to any component of JR-141.
* A patient who has a known or suspected local or general infection or is at risk of abnormal bleeding due to medical conditions or therapies.
* A patient who has documented mutation of other genes, including loci adjacent to the IDS gene that are known to be associated with developmental delay, seizures, or other significant CNS disorders.
* A patient who has documented loss of activity of sulfatases other than IDS.
* A patient who has had a ventriculoperitoneal shunt placed or any other brain surgery, or has a clinically significant ventriculoperitoneal shunt malfunction within 30 days of screening.
* A patient who is full time employee of the sponsor or research site personnel directly affiliated with this study or their immediate family members.
* A patient who otherwise is judged by the principle investigator or sub-investigator to be ineligible to participate in the study.
* The subject has a positive pregnancy test or is breastfeeding at screening or randomization.

\[Only in France\]

* Persons deprived of their liberty by a judicial or administrative decision, according to article L.1121-6 the Public Health Code (Code de la santé publique), adults who are the subject of a measure of legal protection or unable to express their consent according to article L. 1121-8 of the Code de la santé publique)
Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

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JCR Pharmaceuticals Co., Ltd.

INDUSTRY

Sponsor Role lead

Responsible Party

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Responsibility Role SPONSOR

Locations

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Phoenix Children's Hospital

Phoenix, Arizona, United States

Site Status

UCSF Benioff Children's Hospital Oakland

Oakland, California, United States

Site Status

Ann & Robert H. Lurie Children's Hospital of Chicago

Chicago, Illinois, United States

Site Status

University of Minnesota

Minneapolis, Minnesota, United States

Site Status

Columbia University

New York, New York, United States

Site Status

University of North Carolina at Chapel Hill Medical School Wing E

Chapel Hill, North Carolina, United States

Site Status

Children's Hospital of Philadelphia

Philadelphia, Pennsylvania, United States

Site Status

Hospital Universitario Austral

Buenos Aires, , Argentina

Site Status

Hospital de Clínicas de Porto Alegre

Porto Alegre, , Brazil

Site Status

Instituto de Medicina Integral Prof. Fernando Figueira - Imip

Recife, , Brazil

Site Status

Instituto de Genética e Erros Inatos do Metabolismo

São Paulo, , Brazil

Site Status

Fundación Cardio Infantil - Instituto de Cardiología

Bogotá, , Colombia

Site Status

Hôpital Femme Mère Enfant

Bron, , France

Site Status

Chu De Montpellier Hopital Gui De Chauliac

Montpellier, , France

Site Status

Hôpital Armand Trousseau

Paris, , France

Site Status

Universitätsklinikum Giessen

Giessen, , Germany

Site Status

Universitätsklinikum Hamburg-Eppendorf

Hamburg, , Germany

Site Status

SphinCS GmbH

Höchheim, , Germany

Site Status

Universitätsmedizin Mainz

Mainz, , Germany

Site Status

Ha'Emek Medical Center

Afula, , Israel

Site Status

The Chaim Sheba Medical Center

Ramat Gan, , Israel

Site Status

Fondazione IRCCS San Gerardo dei Tintori

Monza, , Italy

Site Status

Osp. Pediatrico Bambino Gesù, IRCCS

Rome, , Italy

Site Status

Uniwersytecki Szpital Dziecięcy

Krakow, , Poland

Site Status

Hospital Sant Joan de Déu

Barcelona, , Spain

Site Status

Hospital Universitario Virgen del Rocio

Seville, , Spain

Site Status

Gazi University Medicine Faculty Hospital

Ankara, , Turkey (Türkiye)

Site Status

Ege University Children Hospital

Izmir, , Turkey (Türkiye)

Site Status

Great Ormond Street Hospital for Children NHS Trust - Metabolic Medicine

London, , United Kingdom

Site Status

Countries

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United States Argentina Brazil Colombia France Germany Israel Italy Poland Spain Turkey (Türkiye) United Kingdom

Other Identifiers

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JR-141-GS31

Identifier Type: -

Identifier Source: org_study_id

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