Onasemnogene abeparvovec is used to treat spinal muscular atrophy in children younger than 2 years old who have a specific gene mutation that affects nerve signals to the muscles.

onasemnogene abeparvovec may not be effective in a child who is completely paralyzed or is dependent on a ventilator for breathing.

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

onasemnogene abeparvovec can cause serious liver damage, especially in children who already have liver problems. Your doctor will perform blood tests to make sure your child does not have conditions that would make it unsafe to receive onasemnogene abeparvovec.

Your doctor will perform blood tests to make sure your child does not have conditions that would make it unsafe to receive onasemnogene abeparvovec.

Onasemnogene abeparvovec is given as an infusion into a vein, usually only one time. A healthcare provider will give your child this injection.

onasemnogene abeparvovec must be given slowly, and the infusion can take about 1 hour to complete.

Your child may be given steroid medication to help prevent serious side effects of onasemnogene abeparvovec. Keep giving your child the steroid for as long as your doctor has prescribed. The doctor may gradually reduce the dose as your child continues taking the steroid.

Your child will need frequent blood tests to check his or her liver function.

Your child may need to be vaccinated against respiratory syncytial (sin-SISH-ul) virus, or RSV. Follow the doctor's instructions about this vaccination.

If your child vomits shortly after taking the steroid medicine, do not take another dose. Call the doctor for instructions.

Usual Pediatric Dose for Spinal Muscular Atrophy:

Prior to infusion:
-Assess liver function by clinical examination and laboratory testing (ALT, AST, total bilirubin, and prothrombin time)
-Obtain creatinine, complete blood count (including hemoglobin and platelet counts), and troponin-I
-Assess for the presence of anti-AAV9 antibodies

Corticosteroid
-Initiate systemic corticosteroids 1 day prior to IV infusion and continue for a total of 30 days (equivalent to oral prednisolone 1 mg/kg/day)

Single-dose: 1.1 x 10(14) vector genomes/kg IV through a venous catheter over 60 minutes

Comments:
-See Other comments/Administration advice for guidance on administration; the manufacturer's product labeling provides a dose table which includes dose volume (mL) based on weight.
-The use in patients with advance spinal muscular atrophy (e.g., complete paralysis of limbs, permanent ventilator-dependence) has not been evaluated.
-The safety and effectiveness of repeat administration have not been evaluated.

Use: For the treatment of patients less than 2 years with spinal muscular atrophy with bi-allelic mutations in the survival motor neuron 1 gene; because concomitant treatment with corticosteroids may adversely affect neurological development, infusion should be delayed until corresponding full-term gestational age is reached.

This medicine can cause serious liver damage. Tell your doctor if your child has ever had liver problems.

It may not be safe to breastfeed your child while he or she is receiving this medicine. Ask your doctor about any risk.

Onasemnogene abeparvovec is used as a single dose and does not have a daily dosing schedule.

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

If your child is also taking steroid medicine, the child should not receive certain vaccines. If your child is due for any vaccine, ask your doctor first before your child gets the shot(s).

Onasemnogene abeparvovec can pass into your child's stools (bowel movements). For at least 1 month after your child receives a dose, avoid allowing the child's stools to come into contact with hands or other surfaces. Wear rubber gloves while cleaning up the child's body fluids, handling contaminated trash or laundry, or changing diapers. Seal used diapers in disposable bags and throw them into the trash. Wash hands before and after removing gloves. Wash soiled clothing and linens separately from other laundry.

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

Call your doctor at once if your child has:

• jaundice (yellowing of the skin or eyes); or

• easy bruising, unusual bleeding, purple or red spots under your skin.

Common side effects of onasemnogene abeparvovec may include:

• vomiting; or

• abnormal liver function tests.

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 affect onasemnogene abeparvovec, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your child's current medicines and any medicine the child starts or stops using.