New hope for hunter syndrome: Brain-Targeting drug in final testing
NCT ID NCT04573023
First seen Jun 26, 2026 · Last updated Jun 27, 2026 · Updated 1 time
Summary
This Phase 3 study tests a new drug called JR-141 against the current standard treatment (idursulfase) in 86 people with Hunter syndrome (MPS II). The goal is to see if JR-141 can better reduce harmful substances in the brain and improve thinking skills. Participants can switch treatments if their condition worsens in certain ways. The trial is active but no longer recruiting.
What this could mean
Our plain-language read of the trial. This is informational only — not medical advice or a prediction.
Active substance
JR-141 (a drug given by IV infusion weekly)
What this could lead to
If it works, JR-141 could offer better control of both brain and body symptoms of Hunter syndrome than current treatment.
What could go wrong
This is a Phase 3 trial, but results are not yet reported. The drug may not prove superior to existing therapy, and switching rules add complexity. Risks include infusion reactions and unknown long-term effects.
Disclaimer
Read more
Show less
This is a summary of
the original study
.
Summaries may miss details or leave out important information. Before applying or accepting participation, make sure you have read and understood the full study. Curemydisease.com takes no responsibility whatsoever for anything missed, misunderstood, or acted upon as a result of our summary — we know it does not capture everything.
This is a summary of the original study . Summaries may miss details or leave out important information. Before applying or accepting participation, make sure you have read and understood the full study. Curemydisease.com takes no responsibility whatsoever for anything missed, misunderstood, or acted upon as a result of our summary — we know it does not capture everything.
Get updates
Get notified about this study
Sign up to get updates when this study changes or when new studies for MUCOPOLYSACCHARIDOSIS II are added.
By submitting, you agree to our Terms of use
Conditions
The condition(s) this trial relates to.
As listed by the trial registrant
The condition terms exactly as the trial's registrant entered them.
Contacts and locations
Show contact details
Enter your email to view the contact information for this study.
By submitting, you agree to our Terms of use
Locations
-
Ann & Robert H. Lurie Children's Hospital of Chicago
Chicago, Illinois, 60611, United States
-
Children's Hospital of Philadelphia
Philadelphia, Pennsylvania, 19104, United States
-
Chu De Montpellier Hopital Gui De Chauliac
Montpellier, France
-
Columbia University
New York, New York, 10032, United States
-
Ege University Children Hospital
Izmir, Turkey (Türkiye)
-
Fundación Cardio Infantil - Instituto de Cardiología
Bogotá, Colombia
-
Gazi University Medicine Faculty Hospital
Ankara, Turkey (Türkiye)
-
Great Ormond Street Hospital for Children NHS Trust - Metabolic Medicine
London, United Kingdom
-
Ha'Emek Medical Center
Afula, Israel
-
Hospital Sant Joan de Déu
Barcelona, Spain
-
Hospital Universitario Austral
Buenos Aires, Argentina
-
Hospital de Clínicas de Porto Alegre
Porto Alegre, Brazil
-
Hôpital Armand Trousseau
Paris, France
-
Hôpital Femme Mère Enfant
Lyon, France
-
Instituto de Genética e Erros Inatos do Metabolismo
São Paulo, Brazil
-
Osp. Pediatrico Bambino Gesù, IRCCS
Rome, Italy
-
Phoenix Children's Hospital
Phoenix, Arizona, 27599-7487, United States
-
SphinCS GmbH
Höchheim, Germany
-
UCSF Benioff Children's Hospital Oakland
Oakland, California, 94609, United States
-
University of Minnesota
Minneapolis, Minnesota, 55455, United States
-
University of North Carolina at Chapel Hill Medical School Wing E
Chapel Hill, North Carolina, 27599-7487, United States
-
Universitätsklinikum Giessen
Giessen, Germany
-
Universitätsklinikum Hamburg-Eppendorf
Hamburg, Germany
-
Universitätsmedizin Mainz
Mainz, Germany
-
Uniwersytecki Szpital Dziecięcy
Krakow, Poland