Children treated before showing SMA symptoms (presymptomatic)
Lucy has 2 copies of SMN2 gene
Treated at 1½ months old
ZOLGENSMA® (onasemnogene abeparvovec-xioi) has been clinically proven to stop the progression of spinal muscular atrophy (SMA) and stop motor neuron loss with just one dose.
ZOLGENSMA was studied in children who were not showing symptoms (presymptomatic) of SMA in a trial called SPR1NT. The trial studied the safety and efficacy of ZOLGENSMA in children with 2 and 3 copies of the SMN2 backup gene. The main goal of this study was to see the number of children who could sit for 30 seconds or more (for children with 2 copies) and stand without support for 3 seconds or more (for children with 3 copies). The SPR1NT study also looked at how well children could perform specific motor skills, maintain weight without feeding support, and breathe on their own (respiratory status).
Children with 2 copies of SMN2 gene
Who Was Studied
14 children with 2 copies of the SMN2 backup gene and no known symptoms of SMA participated in the study. All were under 6 weeks old—their average age was 20.6 days.
This study followed children up to 18 months of age.
What Were the Goals of the Study?
The main goal for this study was to look at the ability of children to sit independently (functional, independent sitting) for ≥30 seconds (Bayley-III* item 26) before they were 18 months old.
The SPR1NT study also evaluated event-free† survival in children at 14 months of age, as well as the ability to maintain their weight at or above the 3rd percentile without nutritional support before they were 18 months old. This is based on WHO Child Growth Standards.‡
*Bayley Scales of Infant and Toddler Development, 3rd edition (Bayley-III).
†Without the need for permanent ventilation support consisting of ≥16 hours of respiratory assistance per day continuously for ≥14 days.
‡The World Health Organization (WHO) created the WHO Child Growth Standards to chart physical growth.
Sit independently
(14/14) children with 2 copies of SMN2 could sit independently
(30 seconds or more) as measured by Bayley-III at or before the 18-months-of-age study visit
In the natural history (untreated) of SMA type 1, children are not able to sit.
Stand Without Assistance
(10/14) children stood without assistance (10 seconds or more) as measured by WHO MGRS
5/10 did so within an age-appropriate time.
Walk Without Assistance
(10/14) children walked without assistance (5 steps or more) as measured by WHO MGRS
6/10 did so within an age-appropriate time.
CHOP INTEND|| Score
(14/14) children reached a CHOP INTEND|| score of 58 or higher at any visit up to 18 months of age and 93% (13/14) achieved a score of 60 points or higher
||Children had improvement in motor function as assessed by CHOP INTEND, or the Children’s Hospital of Philadelphia Infant Test of Neuromuscular Disorders. This test was created to measure the motor development of children with SMA type 1. The CHOP INTEND scale ranges from 0 to 64, with higher scores indicating better function.
Gross Motor Skills¶
(9/14) children had gross motor skills similar to same-aged children without SMA at the end of the study
Gross motor function was measured by the Bayley Scales of Infant and Toddler Development, a well-accepted, standardized tool to assess the development of children between the ages of 1 and 42 months and compared to a standardized norm. Part of this tool looks at the ability to make large muscle movements, like moving from one place to another.
¶Movement of large muscles in arms, legs, and torso.
Fine Motor Skills
(14/14) children had fine motor skills similar to same-aged children without SMA at the end of the study
Bayley-III Fine Motor Scores were used to determine children’s fine motor skills compared to what is expected for a typical developing child. This tool looks at the ability to make small muscle movements, like grasping and holding objects.
Survival/Breathe Without Support
(14/14) children were alive and free of permanent ventilation
Permanent ventilation means a tracheostomy or the need for a machine to help with breathing for at least 16 hours a day for 2 weeks or more.
Maintain Weight
(13/14) children in the 2-copy group maintained a normal weight (≥3rd percentile for age and gender)
This study determined whether children were able to maintain weight within a normal range (at or above the 3rd percentile for age and gender as defined by WHO guidelines) without the need for non-oral/mechanical feeding support at any visit up to 18 months of age (which was the end of the study).
Children with 3 copies of SMN2 gene
Who Was Studied
15 children with 3 copies of the SMN2 backup gene and no known symptoms of SMA participated in the study. Their average age was 28.7 days.
This study followed children up to 24 months of age.
What Were the Goals of the Study?
The main goal for this study was to look at the ability of children to stand without support for ≥3 seconds (Bayley-III* item 40) before they were 24 months old.
The SPR1NT study also evaluated the ability of children to walk alone (Bayley-III item 43) before they were 24 months of age.
*Bayley Scales of Infant and Toddler Development, 3rd edition (Bayley-III).
Stand Without Assistance: 3 seconds or more
(15/15) children stood without assistance (3 seconds or more) as measured by Bayley-III at or before the 24-months-of-age study visit
14/15 achieved this milestone within an age-appropriate time.
Walk Without Assistance
(14/15) children walked without assistance (5 steps or more) as measured by Bayley-III
11/14 did so within an age-appropriate time.
Stand With Assistance: 10 seconds or more
(14/15) children stood with assistance (10 seconds or more) as measured by WHO MGRS
11/14 children achieved this milestone within an age-appropriate time.
Motor Skills
(15/15) children had gross and fine motor scores similar to children of the same age without SMA during at least one visit
Gross and fine motor function was measured by the Bayley Scales of Infant and Toddler Development, a well-accepted, standardized tool to assess the development of children between the ages of 1 and 42 months and compared to a standardized norm. Gross motor function is the ability to make large muscle movements, like moving from one place to another. Fine motor function is the ability to make small muscle movements, like grasping and holding objects.
Motor Skills
(9/10) children had gross and fine motor skills similar to same-aged children without SMA at the end of the study
Breathe Without Support
(15/15) children were alive and free of permanent breathing support
Permanent ventilation means a tracheostomy or the need for a machine to help with breathing for at least 16 hours a day for 2 weeks or more.
Feed Without Support
(15/15) children did not require feeding support
See the safety profile of ZOLGENSMA
As of 2020, experts recommend all babies diagnosed with SMA at birth and who have 2 to 4 copies of SMN2 should be treated for SMA as early as possible in order to stop disease progression—whether or not they are showing symptoms.
Get your child started with ZOLGENSMA.