For Healthcare Professionals

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Supporting your MPS II journey


ELAPRASE dosing and infusion set up

Nurse preparing an ELAPRASE infusion

The dose of ELAPRASE given depends on your weight, so you should be regularly weighed to calculate the optimal dose. ELAPRASE is a weekly infusion therapy, which means it’s given intravenously (by IV).

To receive ELAPRASE therapy, you will have to go to a treatment center every week. At the treatment center, a healthcare professional will administer the therapy and can answer any questions you may have.

Typically, the infusion can take up to 3 hours, but patients may require longer infusion times if hypersensitivity reactions occur. There also may be additional time for preparation and observation. Your healthcare provider can give you more details about what to expect and can help you plan ahead.

Each infusion center has its own guidelines about what patients are permitted to do while undergoing therapy, and it may be OK to engage in a quiet activity, such as reading a book, watching TV, or doing homework. Check with your treatment center before you arrive to find out what activities are acceptable.

Patients who tolerate the infusions well may be able to gradually shorten infusion time to 1 hour.

Where permitted by local healthcare and reimbursement policy, patients who tolerate ELAPRASE infusions well over several months may be able to receive infusions at home under the supervision of a healthcare professional. Speak to your doctor about home infusions.

As with any new experience, the ELAPRASE infusion might be unfamiliar at first, or the process might even make you nervous. Talk to your doctor about any concerns you have.

ELAPRASE patient during an infusion
Important Safety Information


Some patients have experienced serious allergic reactions (including life-threatening anaphylactic reactions) during and up to 24 hours after treatment, regardless of how long they were taking ELAPRASE. Anaphylactic reactions are immediate and include breathing problems, low oxygen levels, low blood pressure, hives and/or swelling of the throat or tongue. If a patient (you or your child) has experienced an anaphylactic reaction, the patient may require an extended period of observation by the patient’s healthcare team. If you or your child has breathing problems, a fever, or a respiratory illness, you or your child may be at risk of life-threatening worsening of those conditions due to allergic reactions from ELAPRASE. Your healthcare team should be advised of those conditions before treatment with ELAPRASE because the information may affect the timing of ELAPRASE treatment.

You or your child should be closely watched during and after ELAPRASE treatment and you should confirm with your healthcare team in advance of treatment that it is prepared to manage serious allergic reactions, including anaphylactic reactions. Tell your healthcare team immediately if any signs of an allergic reaction happen. Those signs may include breathing problems, low blood pressure, rash, hives, itching, flushing, fever and/or headache.

When serious allergic reactions happened during clinical trials, later ELAPRASE treatments were managed with allergy-controlling drugs before or during treatment, a slower rate of ELAPRASE treatment, and/or early discontinuation of treatment.

Children with serious genetic mutations may be at risk for allergic reactions, serious side effects and antibody development. In a clinical study of children 7 years and younger, patients with certain types of genetic mutations experienced a higher number of allergic reactions, serious side effects, and development of an immune response to treatment. This immune response may interfere with the effectiveness of ELAPRASE. Talk to your healthcare team about whether you or your child may be at risk.

If you or your child has breathing problems, other respiratory illness, heart problems, or susceptibility to fluid overload, you or your child may be at higher risk of fluid overload during ELAPRASE treatment. Your healthcare team should be advised of those problems before treatment and you should confirm with your healthcare team in advance of treatment that it is appropriately trained to watch for signs of fluid overload and provide the necessary medical support. Patients at risk for fluid overload may require longer observation time.

What are possible side effects of ELAPRASE?
The most common side effects of ELAPRASE include:

  • In patients aged 5 and older:
    • - Headache
    • - Itching
    • - Muscle and bone pain
    • - Hives
    • - Diarrhea
    • - Cough
  • In patients aged 7 years or younger:
    • - Fever
    • - Rash
    • - Vomiting
    • - Hives

The most common side effects needing medical attention were allergic reactions, and included rash, hives, itching, flushing, fever, and headache. Tell your healthcare team immediately if any signs of an allergic reaction happen. These are not all the possible side effects of ELAPRASE.

What is ELAPRASE (idursulfase)?

ELAPRASE is a prescription medicine for patients with Hunter syndrome. ELAPRASE has been shown to improve walking ability in patients 5 yrs and older. In patients 16 months to 5 years old, ELAPRASE did not show improvement in disease-related symptoms or long-term clinical results; however, treatment with ELAPRASE has reduced spleen size similarly to patients 5 yrs and older. It is not known if ELAPRASE is safe and effective in children under 16 months old.