A Study of ELAPRASE in Treatment-naïve Participants With Hunter Syndrome (Mucopolysaccharidosis [… (NCT05494593) | Clinical Trial Compass
WithdrawnPhase 4
A Study of ELAPRASE in Treatment-naïve Participants With Hunter Syndrome (Mucopolysaccharidosis [MPS] II)
Stopped: Study was closed due to enrollment challenges
United States0Started 2023-02-28
Plain-language summary
The main aim of this study is to evaluate the ability of a prophylactic immune tolerizing regimen (ITR) to prevent or reduce the development of high titer anti-idursulfase antibodies in treatment-naïve participants with Hunter syndrome.
In this open label, single arm study, all participants will receive ELAPRASE treatment and a prophylactic ITR.
Participants will be treated with ELAPRASE for up to 104 weeks. The prophylactic ITR will start 1 day prior to the start of ELAPRASE. The prophylactic ITR will consist of a 5-week cycle of: Rituximab (intravenously \[IV\], weekly for 4 weeks); Methotrexate (oral, 3 times per week for 5 weeks) and intravenous immunoglobulin (IVIG) (IV, every 4 weeks of the cycle).
Following the completion of 1 cycle, an assessment will be made at Month 6, 12, and 18 regarding the need for administering another 5-week cycle of the ITR.
Participants will be in the study for approximately 112 weeks (including 6 weeks for screening, up to 104 weeks for treatment, and 2 weeks for follow-up).
Who can participate
Age range
6 Years
Sex
MALE
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion Criteria:
* Participant is male.
* Participant is ELAPRASE-naïve at study entry.
* Participant must have a documented diagnosis of MPS II. The following combination will be accepted as diagnostic of MPS II:
* Participant has a deficiency in iduronate-2-sulfatase (I2S) enzyme activity of less than or equal to (\<=) 10 percent (%) of the lower limit of the normal range as measured in plasma, fibroblasts, or leukocytes (based on the reference laboratory's normal range). The participant has a normal enzyme activity level of at least 1 other sulfatase as measured in plasma, fibroblasts, or leukocytes (based on the reference laboratory's normal range).
* Participant has a documented mutation in the IDS gene; additionally, participants must have a severe mutation (example, large deletion or complex gene rearrangement), which is predicted to lead to development of a persistent anti-idursulfase antibody response.
* Participant will be less than (\<) 6 years of age at enrollment.
* Participant has a negative test result for serum anti-idursulfase antibodies.
Exclusion Criteria:
* Participant has received treatment with any investigational drug within the 30 days prior to study entry.
* Participant has received or is receiving treatment with idursulfase-IT.
* Participant has received growth hormones, a cord blood infusion, or a bone marrow transplant at any time.
* Participant has received blood product transfusions within 90 days prior to screening.
* Participant is u…
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Rate of Anti-Idursulfase Antibodies Formation, Including Anti-Idursulfase Antibodies That Have Enzyme Neutralizing Activity