RecruitingPhase 1NCT02254863
Metabolic
Hunter Syndrome
Also known as MPS II, mucopolysaccharidosis type II, IDS deficiency, iduronate-2-sulfatase deficiency
Hunter syndrome (MPS II) is an X-linked lysosomal storage disorder caused by deficiency of iduronate-2-sulfatase (IDS), leading to accumulation of dermatan sulfate and heparan sulfate. It affects almost exclusively males.
9
studies recruiting now
as of 7 Sept 2026
83
studies registered in total
as of 7 Sept 2026
2
countries with a recruiting site
as of 7 Sept 2026
14 Sept 2023
most recent study posted
among recruiting studies
Recruiting trials
RecruitingNCT05619900
Registry of Patients Diagnosed With Lysosomal Storage Diseases
RecruitingPhase 1NCT04532047
PEARL (PrEnAtal Enzyme Replacement Therapy for Lysosomal Storage Disorders)
RecruitingNCT06036693
MPS (RaDiCo Cohort) (RaDiCo-MPS)
RecruitingNCT03333200
Longitudinal Study of Neurodegenerative Disorders
Showing the 5 most recently updated recruiting studies, as recorded 7 Sept 2026. Live status on each study page.
See all 9 recruiting studiesWhere recruiting studies are running
Countries with at least one recruiting site among the studies above, 7 Sept 2026. Tap a country to search trials there.
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About Hunter Syndrome
Hunter syndrome (MPS II) is an X-linked lysosomal storage disorder caused by deficiency of iduronate-2-sulfatase (IDS), leading to accumulation of dermatan sulfate and heparan sulfate. It affects almost exclusively males. The severe form includes progressive neurodegeneration with behavioral problems and intellectual decline, while the attenuated form spares cognitive function. Idursulfase (Elaprase) is approved as intravenous ERT; intrathecal idursulfase beta is approved in Japan for the neuronopathic form.
Common clinical features
Coarse facial featuresHepatosplenomegalyJoint stiffnessProgressive intellectual decline (severe form)Obstructive airway diseaseHearing lossCardiac valve disease
From Orphanet’s phenotype annotations (CC BY 4.0). Not a complete list.
Treatments being studied
3 approved treatments and 4 in clinical development, from Open Targets (CC BY 4.0). Not medical advice.
Approved: Idursulfase BetaApproved: Pabinafusp AlfaApproved: Idursulfase (Elaprase)
Phase 2/3Tividenofusp Alfa
Phase 2/3Cannabidiol (Epidiolex)
Phase 2/3Somatropin (Genotropin)
Phase 1/2Anakinra (Antril)
Before you apply
Things trial teams commonly ask about for Hunter Syndrome. Not eligibility rules; those are set by each study.
- Distinguish severe (neuronopathic) from attenuated Hunter syndrome — CNS trials target severe form; somatic ERT trials may accept both
- IDS enzyme activity in plasma or leukocytes and urinary heparan/dermatan sulfate are required eligibility biomarkers
- Idursulfase (Elaprase) IV ERT is standard — intrathecal delivery trials require no prior intrathecal therapy
- CNS biomarkers including CSF heparan sulfate and brain MRI findings are key eligibility and outcome measures for neuronopathic trials
Related conditions
Information, not medical advice. Trial listings are shown as recorded on ClinicalTrials.gov; whether any study is right for you is a decision for you and your clinicians, and eligibility is decided by each research team. Disease information from Orphanet (CC BY 4.0).