What is spinal muscular atrophy (SMA)?

SMA is a progressive, rare genetic disease that is caused by the survival motor neuron 1 (SMN1) gene that is missing or not working properly. Learn more about how SMA is inherited, the role of the backup gene, and the signs and symptoms of SMA.

Download the Facts About SMA guide
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What is spinal muscular atrophy (SMA)?

SMA is a progressive, rare genetic disease that is caused by the survival motor neuron 1 (SMN1) gene that is missing or not working properly. Learn more about how SMA is inherited, the role of the backup gene, and the signs and symptoms of SMA.

Download the Facts About SMA guide
  • If diagnosed early, SMA can be treated quickly to stop the progression of the disease.

  • About 1 in 50

    people in the United States (or 6.6 million* Americans) is a genetic carrier of SMA, and most don’t know it.

  • Graphic depicting 1 in 11K

What causes SMA?

The genetic root cause of SMA is the SMN1 gene that is missing or not working properly. When this main gene is missing or not working properly, the body cannot make enough survival motor neuron (SMN) protein, which is needed for motor neuron cell survival. Everyone is born with a certain amount of motor neuron cells, which are responsible for communicating with the arms, legs, throat, and many other areas in the body to tell them to work properly.

Without enough SMN protein, select motor neuron cells throughout the body may lose function and die. As a result, patients with SMA experience muscle weakness and may develop difficulty breathing, swallowing, or speaking.

See how ZOLGENSMA® (onasemnogene abeparvovec-xioi) helped improve breathing, eating, and other motor functions in clinical studies.

The role of a backup gene

There is a backup gene for the SMN1 gene, called the SMN2 gene. People can have 1 or more copies of this backup gene. The SMN2 gene, like the SMN1 gene, tells the body to make SMN protein. For people with SMA, the SMN2 gene is the main source of SMN protein production; however, it is unable to produce as much protein as the SMN1 gene.

In fact, the SMN2 gene makes only about 10% of working SMN protein compared to the protein produced by the SMN1 gene. That is why it is essential to replace the function of the missing or nonworking SMN1 gene.

Even people with several copies of the SMN2 gene may not produce as much SMN protein as those with the working SMN1 gene, and their motor neuron cells may not work as they should. Usually, the more copies of the SMN2 gene a person has, the less severe his or her SMA is.

Learn about the types of SMA
Genetics of a person unaffected by SMA
Genetics of a person living with SMA

ZOLGENSMA targets the genetic root cause of SMA with a one-time dose

HOW ZOLGENSMA WORKS

Learn how ZOLGENSMA replaces the function of the SMN1 gene to treat SMA

Read the transcript

Scientific innovation has led to some pretty incredible breakthroughs in modern medicine. And today, we’re going learn about one of those amazing breakthroughs—a gene therapy called ZOLGENSMA® (onasemnogene abeparvovec-xioi) that stops the progression of spinal muscular atrophy, or SMA, with a one-time infusion.

Don’t worry, you don’t have to be a scientist to understand it. Let me show you how it works.

Children with SMA are born with a missing or nonworking SMN1 gene. ZOLGENSMA is an infusion that delivers SMN genes where they’re needed, in a child’s body, to help keep the muscles working as they should.

Now that you know the basics, let’s dive in a little deeper to see how ZOLGENSMA works in the body and how it helps children with SMA.

A dedicated team of scientists at Novartis Gene Therapies approached SMA treatment in a bold way—by targeting the genetic root cause of SMA with a one-time infusion.

Why is targeting the genetic root cause so important? Well, the SMN1 gene provides instructions for motor neuron cells to make SMN protein.

Without enough SMN protein, the motor neuron cells stop working—and that's a big problem!

These motor neuron cells are responsible for all types of muscle movement that we rely on daily for eating, breathing, sitting up, walking, or, when you hear a great song, singing.

If there isn’t enough SMN protein being made, motor neurons stop working. Then, these basic functions we rely on become harder to do and can be lost permanently. As you can imagine, the sooner treatment is received, the sooner the progression of SMA can be stopped.

This is where the amazing science behind ZOLGENSMA comes in. ZOLGENSMA is designed to stop the progression of SMA.

The main components of ZOLGENSMA are a gene and a vector.

The gene is a new, fully functioning SMN gene that's just waiting to get to work.

The vector is made from a type of virus called AAV9, which is not known to make people sick.

The viral DNA is removed and replaced with the new SMN gene, which is then delivered to the right places.

Think of the vector as a delivery truck—with its cargo, in this case the new SMN gene, it’s ready to make its delivery to the motor neuron cells. This process happens throughout the body with many new SMN genes getting delivered to their destination.

That’s pretty cool, right? Even cooler is the fact that more than two-thousand children have received ZOLGENSMA.

Thanks for watching. And if you have any questions about ZOLGENSMA, make sure you talk to your doctor.

Close the transcript

How SMA is inherited

SMA is an autosomal recessive disorder. This means that in order to have SMA, a person must have 2 copies of a nonworking SMN1 gene or be missing both copies of the SMN1 gene.

Parents who don’t have SMA but are carriers
25%
chance your child doesn’t have SMA and is not a carrier
50%
chance your child doesn’t
have SMA but is a carrier
25%
chance your child has SMA

Can someone treated with ZOLGENSMA pass SMA to their children?

Treatment with ZOLGENSMA allows people with SMA to make SMN protein. However, they still have 2 nonworking or missing copies of the SMN1 gene. This means that a person who’s been treated with ZOLGENSMA will pass on a nonworking or missing SMN1 gene to any children he or she may have. If this person’s partner is also a carrier, then there is a chance their children will have SMA.

What is a carrier?

A carrier is a person who has 1 healthy copy and 1 nonworking copy of the SMN1 gene that were passed down from the parents. A carrier generally does not show any signs or symptoms of SMA.


How can someone find out if they are a carrier?

To find out if someone is a carrier of SMA, a genetic test is needed. This is performed through a blood test. People with a family history of SMA, which includes a family member with SMA or family member known to be a carrier, should consider getting tested. If you are interested in learning more about what being a carrier means, speak to a genetic counselor or your doctor.

I think that knowledge is power. It’s essential to our children to know as much as we can so we can be prepared to start treatment as soon as possible after birth.

Victoria, mother of Jaxon and Olivia
Download PDF for Facts About SMA

Does my child have SMA?

The Facts About SMA provides you with easy-to-understand information about what causes SMA, signs and symptoms of SMA, and how quickly SMA can progress to a life-threatening condition. Learn more about SMA and bring this PDF to your doctor’s office to determine next steps.

Download the facts

Important Safety Information

What is the most important information I should know about ZOLGENSMA?

  • ZOLGENSMA can increase liver enzyme levels and cause acute serious liver injury or acute liver failure.
  • Patients will receive an oral corticosteroid before and after infusion with ZOLGENSMA and will undergo regular blood tests to monitor liver function.

Important Safety Information

What is the most important information I should know about ZOLGENSMA?

  • ZOLGENSMA can increase liver enzyme levels and cause acute serious liver injury or acute liver failure.
  • Patients will receive an oral corticosteroid before and after infusion with ZOLGENSMA and will undergo regular blood tests to monitor liver function.
  • Contact the patient’s doctor immediately if the patient’s skin and/or whites of the eyes appear yellowish, if the patient misses a dose of corticosteroid or vomits it up, or if the patient experiences a decrease in alertness.

What should I watch for before and after infusion with ZOLGENSMA?

  • Infections before or after ZOLGENSMA infusion can lead to more serious complications. Contact the patient’s doctor immediately if you see any signs of a possible infection such as coughing, wheezing, sneezing, runny nose, sore throat, or fever.
  • Decreased platelet counts could occur following infusion with ZOLGENSMA. Seek immediate medical attention if the patient experiences unexpected bleeding or bruising.
  • Thrombotic microangiopathy (TMA) has been reported to occur approximately one week after ZOLGENSMA infusion. Caregivers should seek immediate medical attention if the patient experiences any signs or symptoms of TMA, such as unexpected bruising or bleeding, seizures, or decreased urine output.

What do I need to know about vaccinations and ZOLGENSMA?

  • Talk with the patient’s doctor to decide if adjustments to the vaccination schedule are needed to accommodate treatment with a corticosteroid.
  • Protection against respiratory syncytial virus (RSV) is recommended.

Do I need to take precautions with the patient’s bodily waste?

Temporarily, small amounts of ZOLGENSMA may be found in the patient’s stool. Use good hand hygiene when coming into direct contact with bodily waste for 1 month after infusion with ZOLGENSMA. Disposable diapers should be sealed in disposable trash bags and thrown out with regular trash.

What are the possible or likely side effects of ZOLGENSMA?

The most common side effects that occurred in patients treated with ZOLGENSMA were elevated liver enzymes and vomiting.

Indication

What is ZOLGENSMA?
ZOLGENSMA is a prescription gene therapy used to treat children less than 2 years old with spinal muscular atrophy (SMA). ZOLGENSMA is given as a one-time infusion into a vein. ZOLGENSMA was not evaluated in patients with advanced SMA.

The safety information provided here is not comprehensive. Talk to the patient’s doctor about any side effects that bother the patient or that don’t go away.

You are encouraged to report suspected side effects by contacting the FDA at 1-800-FDA-1088 or www.fda.gov/medwatch, or Novartis Gene Therapies, Inc. at 833-828-3947.

Please see the Full Prescribing Information.