Hunter Syndrome JR-141 Study



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The purpose of this study is to find out if JR-141, an experimental drug, works better than the standard treatment, idursulfase, for MPS II (Hunter Syndrome) and how safe and effective it is in the management of central nervous system symptoms (such as brain or body function loss) and other body symptoms (including lungs, ears, heart, kidneys, and eyes, as well as any type of liver, bone or joint abnormalities) related to MPS II. Since JR-141 is an investigational drug, it has not been approved by the Food and Drug Administration (FDA).

Who Do I Contact?

If you are interested in participating in the study or want to learn more please contact our study team at baconmc [at] or 267-422-2138. Identifier

Eligibility & Criteria

IRB #:
Official Title:
A Phase III study of JR-141 in Mucopolysaccharidosis type II (Hunter Syndrome) Patients
Study Phase:
Phase II
Eligible Age Range:
30 Months - 99 Years
Study Categories:

Visit Criteria

Study participation is divided into 3 different periods:

  • Screening Period (up to 4 weeks)
  • Treatment Period (104 weeks for Cohort A, 52 weeks for Cohort B)
  • Follow up (1 week)

Subjects who qualify for the study, will be assigned to one of the study cohorts based on age:

  • Cohort A: between 30 months -6 years old
  • Cohort B: 6 years or older

You will be randomly assigned to receive either the investigational drug or the standard treatment.

If there are urgent or significant safety concerns, you may be required to attend additional visits at CHOP.

Throughout the study we will contact you by telephone and/or email to evaluate your safety and conditions; you can always report any issues or concerns to us.