Spinal muscular atrophy (SMA) is a group of serious, progressive diseases that destroys motor neuron cells. SMA treatment aims to reduce symptoms and slow or stop the progression of the disease.

SMA destroys motor neurons, which are critical to most motor functions, such as movement, speaking, and breathing.

However, because SMA is a genetic disease, newer treatments that address the underlying genetics of the disease may help. Gene therapy may prevent additional motor neuron damage, potentially alleviating symptoms if a person gets treatment early enough. This can extend life expectancy and improve quality of life.

However, there is no cure for adults and older children. Gene therapy is also very expensive, and not everyone responds to the treatment.

Read more to learn about the treatments for SMA, new and emerging therapies, and cost and accessibility assistance.

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There is no complete cure for SMA that works for everyone. However, new treatment options have greatly improved outcomes in people with the condition.

Some treatment methods include the below.

Symptom management and supportive care

Historically, treatment for SMA focused on managing symptoms. Some of these options include:

  • Medication: Medications may help improve breathing or muscle function. For example, doctors may give albuterol, valproic acid, or phenylbutyrate. In type 1, the most severe form of SMA, clinical trials have not proven that any medications improve outcomes. It is also important to note that while valproic acid and phenylbutyrate have shown promise, they are not approved treatments for SMA.
  • Rehabilitative therapies: Occupational and physical therapy may help a person retain or regain some functioning, especially in less severe forms of SMA.
  • Surgery: A person may need surgery to correct SMA complications such as scoliosis. Some people with SMA need a surgical gastrostomy to allow them to eat through a tube.
  • Breathing support: Some people with SMA may need breathing support such as a ventilator or bilevel positive airway pressure machine. Others may need a tracheostomy, which involves doctors inserting a tube in a person’s trachea to help them breathe.

Onasemnogene abeparvovec or gene therapy

Onasemnogene abeparvovec, available under the brand name Zolgensma, is a new gene therapy for SMA.

People with SMA have an issue with the function of the survival motor neuron (SMN) gene. Zolgensma replaces this atypical gene with a fully functioning one through an intravenous infusion. This can prevent the further destruction of motor neurons.

However, this treatment is only effective in babies and very young children. So while it offers the first chance of a cure, it cannot cure all or even most cases.


Nusinersen, available under the brand name Spinraza, is an injection that can increase the production of the SMN protein. This can prevent further destruction of motor neurons, stopping the disease from worsening.

However, it does not reverse existing neuron damage. It works best in infants and young children whose symptoms have not yet become severe.

In a phase three clinical trial, 51% of participants hit their motor milestones, compared to none in the placebo group. This demonstrates the potential efficacy of nusinersen.


Risdiplam, available under the brand name Evrysdi, is an oral drug doctors use to treat SMA.

It modifies the process by which the SMN gene splices, which then increases levels of functioning SMN proteins. This can reduce symptoms by slowing the destruction of motor neurons.

In a clinical trial of 21 infants with the most severe form of SMA, 7 of 17 of those in the high dose risdiplam group could sit unassisted for 5 seconds. None of the infants in the low dose group could do so.

The cost of treatment depends on the treatment a person needs, their insurance, their location, and more. While the cost can vary dramatically depending on these factors, many SMA treatments can be very costly.

Gene therapy and nusinersen are the most expensive treatments. Reports have stated that nusinersen can cost approximately $700,000, while the cost for the gene therapy drug onasemnogene abeparvovec is $2.12 million. Risdiplam is also very expensive — annual costs typically range from $93,000 to more than $350,000.

Funding for these treatments varies. Some insurers cover gene therapy, but only for people who meet certain criteria — usually infants and toddlers. Medicare and Medicaid may also offer funding for gene therapy in certain circumstances.

Government health services often provide full or partial funding for SMA treatments. For example, the Ministry of Health in British Columbia announced in 2022 that it would fund risdiplam.

Several organizations provide financial support for families of children with SMA. The SMA Foundation offers extensive resources and guidance about paying for care.

For many people, insurance will cover medically necessary care, but this is not always the case. People with limited or no insurance may have issues accessing care through no fault of their own.

It is also important for families to check insurance policies and explore options for local funding, such as from children’s hospitals, charities, and more.

Gene therapy is still a very new treatment with ongoing research into its efficacy. For now, it can only treat very young children, but with new discoveries, this might change.

Current research focuses on understanding the mechanism that causes the destruction of motor neurons.

Some data from animal studies have identified agents that may halt or reverse the process, but these drugs still require testing in humans. There is also some research that aims to identify biomarkers for SMA that may predict outcomes or treatment responses.

SMA is a chronic, progressive, and potentially fatal illness. No treatment cures the disease for everyone, and curative treatments are only currently only available for infants and very young children.

People with SMA and their families should work with a specialist to develop a comprehensive treatment plan. Parents and caregivers of children with SMA should inquire about gene therapy. This is because it is typically available very early in life and can stop the condition from progressing.