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Generic Name: vestronidase alfa (ves TRON i dase AL fa)
Brand Name: Mepsevii

Medically reviewed by on Dec 5, 2017 – Written by Cerner Multum

What is Mepsevii?

Mepsevii contains an enzyme that occurs naturally in the body in healthy people. Some people lack this enzyme because of a genetic disorder. This medicine helps replace this missing enzyme in such people.

Mepsevii is used to treat some of the symptoms of a genetic condition called mucopolysaccharidosis VII (MYOO-koe-pol-ee-SAK-a-rye-DOE-sis Seven) or MPS VII, also called Sly syndrome.

MPS VII 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 or hearing loss, and changes in mental or physical abilities.

Mepsevii may improve walking ability in people with this condition. However, this medication is not a cure for MPS VII.

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

Important Information

An allergic reaction may occur during or shortly after infusion of Mepsevii. Tell your caregivers or get emergency medical help right away if you have any signs of a severe allergic reaction, such as sweating, trouble breathing, pale skin, blue lips or fingernails, and feeling like you might pass out.

Before taking this medicine

You should not receive Mepsevii if you are allergic to it.

To make sure Mepsevii is safe for you, tell your doctor if you have ever had:

  • a lung disease or breathing problems.

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

It is not known whether vestronidase alfa passes into breast milk or if it could affect the nursing baby. Tell your doctor if you are breast-feeding.

How is Mepsevii given?

Mepsevii is injected into a vein through an IV. A healthcare provider will give you this injection.

Mepsevii is usually given once every 2 weeks.

Mepsevii must be given slowly, and the IV infusion can take up to 4 hours to complete.

About 30 to 60 minutes before each injection, you will be given other medications to help prevent a serious allergic reaction.

Tell your caregivers if you feel any burning, pain, or swelling around the IV needle when Mepsevii is injected.

You will be watched closely for at least 60 minutes after receiving Mepsevii, to make sure you do not have an allergic reaction.

What happens if I miss a dose?

Call your doctor for instructions if you miss an appointment for your Mepsevii.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while receiving Mepsevii?

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

Mepsevii side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

An allergic reaction may occur during or shortly after infusion of Mepsevii. Tell your caregivers or get emergency medical help right away if you have any signs of a severe allergic reaction, such as:

  • feeling like you might pass out, even while lying down;

  • sweating, cold or clammy skin;

  • feeling short of breath;

  • pale skin; or

  • blue lips or fingernails.

Common side effects may include:

  • diarrhea;

  • swelling in your hands or feet;

  • rash, itching; or

  • swelling or irritation around the IV needle.

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.

What other drugs will affect Mepsevii?

Other drugs may interact with vestronidase alfa, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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