Evrysdi shown to stabilize motor, lung function in adults with SMA: Study
Gains were particularly notable in severely affected patients, researchers said
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- Evrysdi treatment for SMA stabilizes motor and lung function in adults over 3 years, a study showed.
- It can modestly improve arm and hand function, and prevent loss of motor function.
- Evrysdi boosts SMN protein levels, preserving motor neuron health to slow SMA progression.
Treatment with Evrysdi (risdiplam) may modestly improve arm function for adults with spinal muscular atrophy (SMA), a new study from the Czech Republic and Slovakia indicates.
Findings suggest that adults with SMA generally have stable motor and lung function over three years of Evrysdi treatment. Evrysdi “was associated with early improvements in upper-limb function that were maintained for 2-3 years, small but consistent gross-motor improvements, no loss of motor function, and no initiation of ventilatory support,” researchers wrote.
The study, “A real-world, multicentre, epidemiological study in Czech and Slovak adults with spinal muscular atrophy treated with risdiplam,” was published in Scientific Reports. The work was funded by Roche, which sells Evrysdi through its subsidiary Genentech.
Evrysdi designed to boost levels of key protein
SMA is mainly caused by mutations in the gene that encodes SMN, a protein vital for the survival of motor neurons, the nerve cells that control movement. Lacking SMN, motor neurons sicken and die, leading to symptoms such as muscle weakness.
Evrysdi is an oral therapy designed to boost SMN protein levels, thereby preserving motor neuron health to slow or stop disease progression. The therapy has been proven in clinical trials to slow SMA progression, but real-world evidence of Evrysdi’s benefits in adults is limited and comes mainly from small groups of patients.
In this study, scientists reported outcomes for 59 adults with SMA who were treated with Evrysdi and followed for three years using the Czech and Slovak Registry of Muscular Dystrophies.
At the start of treatment, patients ranged in age from 17 to nearly 60, and almost all were wheelchair users. Evrysdi treatment started at a median age of 28.5 years, many years after the median disease onset at 1.1 years. About three-quarters had not been treated with Spinraza (nusinersen), and those who were stayed on therapy for almost 28 months.
Most participants had SMA type 2 or type 3, while several had SMA type 1. Of note, most people with SMA type 1 die in infancy without treatment, so the researchers highlighted the importance of understanding treatment outcomes for those few adults living with this severe form of the disease.
Measure of arm, hand function improved over first 6 months
Results showed that mean scores on the Revised Upper Limb Module (RULM), a standardized measure of arm and hand function, improved significantly over the first six months of Evrysdi treatment and then remained stable out to three years of follow-up. The researchers noted that the RULM improvement was below what’s considered clinically meaningful, but they said these data support the idea that Evrysdi may modestly improve arm and hand function, at least for some adults with SMA.
“Our data emphasize stabilization with selective functional improvements as a clinically meaningful goal in advanced adult SMA patients and endorse RULM as a sensitive endpoint for monitoring therapy outcomes,” the scientists wrote.
Other measures of motor and lung function were generally unchanged or showed a trend toward improvement during Evrysdi treatment. The researchers noted that none of the patients lost motor function or started using a ventilator while on Evrysdi. One patient who wasn’t able to hold their head up before Evrysdi treatment gained this ability after starting on the oral therapy.
These functional gains were particularly notable in severely affected individuals, in whom standardized motor scales may exhibit floor effects and may not fully capture subtle but clinically important changes
Several patients reported noteworthy improvements during daily activities, including less fatigue, increased endurance, greater ability to handle objects and to take care of themselves, and greater capacity to work or engage in educational activities.
“These functional gains were particularly notable in severely affected individuals, in whom standardized motor scales may exhibit floor effects and may not fully capture subtle but clinically important changes,” the scientists wrote.
These results contrast with the typical course of untreated SMA, in which motor function typically worsens over time as the disease progresses. Overall, the data support the idea that Evrysdi treatment can stabilize functional abilities in adults with SMA, the researchers said, noting that such stabilization is an important clinical goal in adults with advanced SMA.
