Skip to main content

Spinal muscular atrophy (SMA) is a serious but treatable disease


SMA is a rare genetic neuromuscular disease caused by deletions or mutations of the survival motor neuron 1, or SMN1 gene, which is critical for normal function of motor neurons.1

Without treatment, SMA is characterized by progressive muscular atrophy, and in its most severe forms, premature death. Today, there are several treatment options for SMA that give patients a chance to achieve unprecedented outcomes.1

Early signs of SMA Type 1 in patients who are untreated


SMA Symptoms

At birth, infants may appear normal, but can develop some of these signs as they age5-7:

  • Muscle weakness and hypotonia

  • Areflexia

  • Impaired head control

  • Reduced bulbar function, including impaired swallowing, feeding, and weak cry and cough

  • Paradoxical breathing, also known as “belly breathing”

  • Bell-shaped chest due to intercostal muscle weakness

  • Progressive respiratory failure requiring noninvasive ventilation (NIV)

  • Missed motor milestones

Hero Banner Lucy

While most patients will be identified through newborn screening, it is still important to rule out SMA if a patient is presenting with these symptoms

The changing SMA landscape


Improvements in identifying and treating SMA have significantly altered the natural history of the disease. Newborn screening has enabled early identification and early treatment. Learn from SMA experts about the future of SMA care.1

Dr. Rocha

"We are now facing a different type of disease than the one that we used to face before the treatment."

— Dr. Tesi Rocha, Medical Director, Neuromuscular Clinic

References: 1. Kirschner J, Bernet G, Butoianu N, et al. Eur J Paediatr Neurol. 2024;8(51):73-78. 2. Data on file. AveXis, Inc. 2020. 3. Curesma.org. https://curesma.org. Accessed February 21, 2023. 4. Oskoui M, Darras BT, De Vivo DC. Chapter 1—Spinal muscular atrophy: 125 years later and on the verge of a cure. In: Sumner CJ, Paushkin S, Ko CP, eds. Spinal Muscular Atrophy. Amsterdam, the Netherlands: Elsevier; 2017. 5. Kolb SJ, Kissel JT. Spinal muscular atrophy. Neurol Clin. 2015;33(4):831-846. 6. Wirth B, Karakaya M, Kye MJ, Mendoza-Ferreira N. Twenty-five years of spinal muscular atrophy research: from phenotype to genotype to therapy, and what comes next. Annu Rev Genomics Hum Genet. 2020;21:231-261. 7. Wang CH, Finkel RS, Bertini ES, et al; Participants of the International Conference on SMA Standard of Care. Consensus statement for standard of care in spinal muscular atrophy. J Child Neurol. 2007;22(8):1027-1049.