SPR1NT Trial Results
SPR1NT Trial Results
Page last checked: 22nd November 2022
Last updated: 23rd June 2022
SPR1NT was a Phase III, multi-centre, single-arm study that investigated the efficacy and safety of onasemnogene abeparvovec (Zolgensma) in pre-symptomatic children with SMN1 mutations and either two or three copies of the SMN2 “back-up” gene. The participants were treated at 6 weeks of age or younger.
SPR1NT Trial participants were divided into 2 cohorts based on SMN2 copy number:
- Cohort 1: 14 babies with two copies of SMN2 expected to develop SMA
- Cohort 2: 15 babies with three copies of SMN2 expected to develop SMA
The Results
Efficacy was compared with a matched natural-history cohort (23 babies).
Cohort 1:
- All 14 enrolled infants sat independently for 30 seconds or more, at any visit ≤18 months
- All survived without permanent ventilation at 14 months
- 13 maintained body weight through 18 months
- No child used nutritional or respiratory support
- No serious adverse events were considered related to treatment by the investigator
Cohort 2:
- All 15 children with three SMN2 copies treated before symptom onset, stood independently before 24 months (14 within the normal developmental window)
- 14 walked independently (11 within the normal developmental window)
- All survived without permanent ventilation at 14 months
- 10 maintained body weight without feeding support through 24 months
- None required nutritional or respiratory support
- No serious adverse events were considered treatment-related by the investigator
Conclusion
Onasemnogene abeparvovec was effective for, and well-tolerated by, pre-symptomatic infants at risk of SMA Type 1 or Type 2, highlighting the urgency for early identification (newborn screening) and intervention.
Strauss, K.A., Farrar, M.A., Muntoni, F. et al. Onasemnogene abeparvovec for presymptomatic infants with two copies of SMN2 at risk for spinal muscular atrophy type 1: the Phase III SPR1NT trial. Nat Med 2022 Jun 17.
Strauss KA, Farrar MA, Muntoni F. et al. Onasemnogene abeparvovec for presymptomatic infants with three copies of SMN2 at risk for spinal muscular atrophy: the Phase III SPR1NT trial. Nat Med 2022 Jun 17.
2020
27th March: Interim SPR1NT data showed that Zolgensma treatment was resulting in the achievement of age-appropriate motor milestones. Nearly all children required no feeding support. Most remained within the age-appropriate weight range. No children required ventilatory support of any kind.
2019
7th May: Phase 3 of the SPR1NT trial, showed motor milestone achievement consistent with normal development. Three serious adverse events occurred but were considered unrelated to treatment.
2018
25th January: AveXis announces SPRINT trial. At this stage it was expected to include about 44 infants less than six weeks of age, who have two to four copies of SMN2.