Idursulfase
Idursulfase is a recombinant enzyme replacement therapy for Hunter syndrome (Mucopolysaccharidosis type II), a rare genetic disorder. It works by replacing the deficient iduronate-2-sulfatase enzyme, breaking down accumulated glycosaminoglycans in cells and reducing the characteristic symptoms of this condition.
Idursulfase is an enzyme replacement therapy for Hunter syndrome that helps break down accumulated sugars in cells.
This medication carries a boxed (black box) warning — the strongest type of FDA warning. Review the full prescribing information before use.
Key facts at a glance
- ATC
- A16AB09
- RxNorm
- 644101
- Generic
- Idursulfase
- Class
- atc-a16
- Brands
- Elaprase
- Availability
- rx
- Lactation
- unknown
- Routes
- —
- Forms
- injection
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Dosage and administration
- Usual dose
- 500mg twice daily
- Maximum
- consult physician
- Frequency
- every 12 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 250mg twice daily
- Maximum
- consult physician
- Frequency
- every 12 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 400mg daily
- Maximum
- consult physician
- Frequency
- once daily
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
Overdose information
Special Populations
8 groupspregnancy
first trimesteravoid if possible
Use only if benefits outweigh potential risks to the fetus. Consider discontinuing therapy if pregnancy occurs.
Regular fetal monitoring including ultrasound examinations
Use with caution and monitor for adverse effects.
pregnancy
second trimesteravoid if possible
Use only if benefits outweigh potential risks to the fetus
Regular fetal monitoring including ultrasound examinations
Use with caution and monitor for adverse effects.
pregnancy
third trimesteravoid if possible
Use only if benefits outweigh potential risks to the fetus. Consider risks of infusion reactions near delivery.
Regular fetal monitoring including ultrasound examinations, closer monitoring in third trimester
Use with caution and monitor for adverse effects.
pediatric_age
pediatricno adjustment
Approved for use in pediatric patients. Standard dosing regimen applies: 0.5 mg/kg weekly via IV infusion
Monitor for infusion-related reactions, regular assessment of disease progression
geriatric
elderlyno specific adjustment
Use with caution. Limited clinical experience in patients over 65 years of age.
Monitor renal and cardiac function closely
Use with caution and monitor for adverse effects.
renal_impairment
renal impairment mildno specific adjustment
Use with caution. No formal studies conducted in patients with renal impairment.
Monitor renal function regularly
Use with caution and monitor for adverse effects.
hepatic_impairment
hepatic impairment mildno specific adjustment
Use with caution. No formal studies conducted in patients with hepatic impairment.
Monitor hepatic function regularly
Use with caution and monitor for adverse effects.
lactation
breastfeedingdiscontinue or avoid
It is unknown whether idursulfase is excreted in human milk. Due to potential risk to infants, breastfeeding should be discontinued or breastfeeding mothers should not receive treatment.
Monitor infant for any adverse effects if mother receives treatment
Statistics and clinical data
Drug class
Idursulfase is a recombinant human iduronate-2-sulfatase enzyme
Indication
Rare genetic lysosomal storage disorder
FDA approval year
First FDA approval for Idursulfase
Administration route
Administered via weekly IV infusion
Hunter syndrome (Mucopolysaccharidosis type II or MPS II), a rare X-linked recessive genetic disorder caused by deficiency of the iduronate-2-sulfatase enzyme
Idursulfase replaces the deficient iduronate-2-sulfatase enzyme, which cleaves the terminal 2-O-sulfate groups from glycosaminoglycans (dermatan sulfate and heparan sulfate), allowing these compounds to be properly metabolized and preventing their harmful accumulation in cellular lysosomes
Administered via intravenous infusion, typically weekly. Requires monitoring for hypersensitivity reactions during infusion. This is a lifelong treatment that helps manage symptoms but is not a cure for the underlying genetic condition.
Contraindications
Conditions and patient states where this medication should be avoided or used with caution.
Do not use (1)
Known allergy to this medication or its components
Use caution (1)
Consult healthcare provider for benefits vs risks assessment
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed July 26, 2026. · Read our editorial policy