Nusinersen works by helping the body produce a protein essential to the function of nerves that control muscle movement. This protein is lacking in people with an inherited disorder called spinal muscular atrophy caused by a mutation in a specific gene.

Nusinersen is used to treat spinal muscular atrophy in adults, children, and infants.

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

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

Your doctor will perform blood and urine tests to make sure you do not have conditions that would prevent you from safely receiving nusinersen.

Nusinersen is injected directly into the fluid that surrounds the brain and spinal cord (cerebrospinal fluid). A healthcare provider will give you this injection.

The nusinersen injection takes about 1 to 3 minutes to complete. You may be given a sedative to help you relax and keep you comfortable during the injection.

Nusinersen is usually given in a series of 4 "loading dose" injections, followed by "maintenance" injections.

The first 3 loading doses are usually given 2 weeks apart, followed by a 4th loading dose given 1 month later. Maintenance doses are then given once every 4 months.

Usual Adult Dose for Spinal Muscular Atrophy:

Loading dose: 12 mg intrathecally every 14 days for 3 doses, then 12 mg intrathecally 30 days after the 3rd dose
Maintenance dose: 12 mg intrathecally once every 4 months

Comments:
-For administration, consider sedation; consider ultrasound or other imaging techniques to guide therapy.
-Prior to administration, remove 5 mL from cerebrospinal fluid; administer as an intrathecal bolus injection over 1 to 3 minutes using a spinal anesthesia needle.
-If a loading dose is delayed or missed, administer it as soon as possible, with at least 14-days between doses and continue dosing as prescribed.
-If a maintenance dose is delayed or missed, administer it as soon as possible and continue dosing every 4 months.

Use: For the treatment of spinal muscular atrophy (SMA)

Usual Pediatric Dose for Spinal Muscular Atrophy:

Loading dose: 12 mg intrathecally every 14 days for 3 doses, then 12 mg intrathecally 30 days after the 3rd dose
Maintenance dose: 12 mg intrathecally once every 4 months

Comments:
-For administration, consider sedation; consider ultrasound or other imaging techniques to guide therapy, especially in younger patients.
-Prior to administration, remove 5 mL from cerebrospinal fluid; administer as an intrathecal bolus injection over 1 to 3 minutes using a spinal anesthesia needle
-If a loading dose is delayed or missed, administer it as soon as possible, with at least 14-days between doses and continue dosing as prescribed.
-If a maintenance dose is delayed or missed, administer it as soon as possible and continue dosing every 4 months.

Use: For the treatment of spinal muscular atrophy (SMA)

You should not be treated with nusinersen if you are allergic to it.

Tell your doctor if you have ever had:

• kidney disease; or

• bleeding problems.

Tell your doctor if you are pregnant or breastfeeding.

Call your doctor for instructions if you miss an appointment for your nusinersen injection. Your dosing schedule may need to be adjusted to allow for enough time between doses.

Since nusinersen 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.

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

Nusinersen may cause serious side effects. Call your doctor at once if you have:

• easy bruising, unusual bleeding (nose, mouth, vagina, or rectum), purple or red pinpoint spots under your skin;

• chest pain, shortness of breath;

• a red skin rash; or

• kidney problems--foamy urine; red or brown colored urine; swelling in your face, stomach, hands, or feet.

Nusinersen may affect growth in children. Tell your doctor if your child is not growing at a normal rate while using nusinersen.

Common side effects of nusinersen may include:

• headache;

• back pain;

• nausea, vomiting, constipation; or

• cold symptoms such as stuffy nose, sneezing, sore throat.

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.

Other drugs may interact with nusinersen, 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.