Idursulfase contains a natural enzyme that some people lack because of a genetic disorder. Idursulfase helps replace this missing enzyme.

Idursulfase is used to treat some of the symptoms of a genetic condition called Hunter's syndrome, also called mucopolysaccharidosis (MYOO-koe-pol-ee-SAK-a-rye-DOE-sis).

Hunter syndrome is a metabolic disorder in which the body lacks the enzyme needed to break down certain natural substances. These substances can build up in the body, causing enlarged organs, abnormal bone structure, changes in facial features, breathing problems, heart problems, vision loss, and changes in mental or physical abilities.

Idursulfase may improve walking ability in people with this condition. However, this medication is not a cure for Hunter syndrome.

Idursulfase may also be used for purposes not listed in this medication guide.

Some side effects may occur during the idursulfase infusion, or up to 24 hours afterward. Get emergency medical help if you have signs of an allergic reaction: feeling like you might pass out; hives; trouble breathing; seizure (convulsions); swelling of your face, lips, tongue, or throat.

Idursulfase is given as an infusion into a vein. A healthcare provider will give you this injection, usually once per week.

This medicine must be given slowly, and the infusion can take up to 3 hours to complete.

Your doctor may also prescribe other medications to help prevent an allergic reaction to idursulfase. Take all of your medications as directed.

Your doctor will need to check your progress on a regular basis.

Usual Adult Dose for Mucopolysaccharidosis Type II:

0.5 mg/kg IV once a week

Comment:
-Clinical studies did not include patients older than 31 years and it is therefore unknown if they respond differently than younger patients.

Use: For the treatment of Hunter syndrome (Mucopolysaccharidosis II [MPS II])

Usual Pediatric Dose for Mucopolysaccharidosis Type II:

16 months or older:
0.5 mg/kg IV once a week

Use: For the treatment of Hunter syndrome (MPS II)

You should not receive this medication if you are allergic to idursulfase.

Tell your doctor if you have asthma or any other lung problems. An allergic reaction could trigger sudden breathing problems.

Your name may be listed on a Hunter Outcome Survey while you are using this medication. The purpose of this registry is to track the progression of this disorder and the effects that idursulfase has on long-term treatment.

It is not known whether idursulfase will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

It may not be safe to breast-feed a baby while you are using this medicine. Ask your doctor about any risks.

Call your doctor for instructions if you miss an appointment for your idursulfase injection.

Since idursulfase is given by a healthcare professional in a medical setting, an overdose is unlikely to occur.

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

Some side effects may occur during the idursulfase infusion, or up to 24 hours afterward. Get emergency medical help if you have signs of an allergic reaction: feeling like you might pass out; hives; trouble breathing, seizure (convulsions); swelling of your face, lips, tongue, or throat.

If you ever have an allergic reaction to idursulfase, you will be watched closely after receiving idursulfase again.

Common side effects of idursulfase may include:

• vomiting, diarrhea;

• headache;

• muscle or joint pain;

• fever, cough;

• itching, rash; or

• flushing (warmth, redness, or tingly feeling).

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.