First Oral Medication Approved for the Treatment of Spinal Muscular Atrophy
If you are anything like me, when I think of muscles, I picture someone at the gym flexing in the mirror, taking their daily gym selfie -#ifyoudontpostitdiditreallyhappen! But our muscles do way more than lift weights.
There are three types of muscle tissue – cardiac, smooth, and skeletal. All of these muscles work to help the body function. But what happens if muscles are weak or start to waste away? When this happens to the muscles used in movement, this is known as spinal muscular atrophy.
There are a few treatment options available for spinal muscular atrophy, but recently the U.S. Federal Drug and Administration (FDA) approved the first oral medication. Check out below to learn more!
What is Spinal Muscular Atrophy?
Spinal muscular atrophy is a genetic disorder where the muscles used for movement become weak or waste away. This condition occurs when there is a loss of motor neurons (specialized nerve cells) that control muscle movement.
Worldwide, spinal muscular atrophy affects 1 per 8,000 to 10,000 people. There are multiple types of spinal muscular atrophy:
- Rarest and most severe form
- Evident before birth
- Most do not survive past infancy due to respiratory failure
- Most common form
- Also known as Werdnig-Hoffmann disease
- Most children cannot control their head movements and may have swallowing problems
- Most do not survive past early childhood due to respiratory failure
- Develops in children between 6 and 12 months old
- Also known as Dubowitz disease
- Most individuals typically cannot stand or walk without support
- Many live into their twenties or thirties
- Also known as Kugelberg-Welander disease
- Develops after early childhood
- Individuals can stand or walk on their own, but over time it becomes more difficult, and they may need to use a wheelchair
- Individuals have a normal life expectancy
- Begins in early adulthood
- Individuals experience mild to moderate muscle weakness, mild breathing problems, and tremors
- Individuals have a normal life expectancy
What is EvrysdiTM?
EvrysdiTM (risdiplam) is a recently approved medication for spinal muscular atrophy in adults and children two months old and up. EvrysdiTM is the first oral medication available for spinal muscular atrophy available in a liquid form, allowing for at-home treatment.
EvrysdiTM comes in an amber bottle and stays in the refrigerator in an upright position. Check with your pharmacist or primary care provider for full instructions and training on how to take or administer EvrysdiTM if you have questions.
How Does it Work?
Remember that a loss of motor neurons causes spinal muscular atrophy. EvrysdiTM works by helping to maintain and make motor neurons, leading to improved motor function.
What are the Side Effects?
The most common side effects include:
Other common side effects explicitly seen in infant-onset spinal muscular atrophy include runny nose/sneezing/sore throat/cough, constipation, lung infection, and vomiting.
This is not a full list of side effects for EvrysdiTM. For more information, contact your primary care provider or pharmacist.
What Do the Studies Say About EvrysdiTM?
The FIREFISH trial looked at infants with type 1 spinal muscular atrophy and investigated the safety and efficacy of EvrysdiTM dosing. This trial found improvement in the majority of the infant’s ability to breathe without permanent support and improvement in slightly less than half of the infant’s ability to sit without support.
The SUNFISH trial looked at children and adults with types 2 or 3 spinal muscular atrophy, investigating the safety and efficacy of EvrysdiTM dosing. The results showed improvement in motor function in children and adults.
The Bottom Line
Spinal muscular atrophy is a genetic condition affecting the muscles involved in movement. It is caused by a loss of motor neurons, specialized neurons that control muscle movement.
EvrysdiTM is the first oral medication approved for the treatment of spinal muscular atrophy. It works by helping to make or maintain motor neurons, improving motor function.
Some of the most common side effects include fever, rash, and diarrhea.
The safety and efficacy of EvrysdiTM were studied in infants and adults with type 1, 2, or 3 spinal muscular atrophy in the FIREFISH and SUNFISH trials.
For more information on how to administer or any questions about EvrysdiTM, contact your primary care provider or pharmacist.
Spinal muscular atrophy. Genetics Home Reference website. https://ghr.nlm.nih.gov/condition/spinal-muscular-atrophy. Updated October 2018. Accessed on September 16, 2020.
About Evrysdi. EvrysdiTM website. https://www.evrysdi.com/about-evrysdi.html. Accessed on September 16, 2020.
EvrysdiTM. Instructions for use. Genentech; 2020.
EvrysdiTM. Package insert. Genentech; 2020.
Investigate Safety, Tolerability, PK, PD and Efficacy of Risdiplam (RO7034067) in Infants With Type1 Spinal Muscular Atrophy (FIREFISH). U.S. National Library of Medicine website. https://clinicaltrials.gov/ct2/show/NCT02913482. Updated August 24, 2020. Accessed September 16, 2020.
A Study to Investigate the Safety, Tolerability, Pharmacokinetics, Pharmacodynamics and Efficacy of Risdiplam (RO7034067) in Type 2 and 3 Spinal Muscular Atrophy (SMA) Participants (SUNFISH). U.S. National Library of Medicine website. https://clinicaltrials.gov/ct2/show/NCT02908685. Updated July 22, 2020. Accessed September 16, 2020.