A groundbreaking study published in The New England Journal of Medicine reveals that initiating oral risdiplam treatment in presymptomatic infants with spinal muscular atrophy (SMA) significantly enhances motor development and survival rates.

The study also found that early risdiplam treatment is well tolerated, with no major adverse effects, and yields better outcomes in children with higher copies of the SMN2 gene and better baseline nerve function.

This positive data supports the use of early intervention with other approved SMA treatments like nusinersen and onasemnogene abeparvovec, which are most effective when started early, reinforcing the push for newborn screening programs.

Most infants with severe SMA type 1 treated early were able to sit by 12 months and walk by 24 months, with all surviving without respiratory support and maintaining feeding abilities after two years.

Risdiplam, approved by the FDA in 2020 for children over two years and extended in 2022 to presymptomatic infants, works by increasing SMN protein production to support motor neuron health.

The RAINBOWFISH study involved infants as young as 16 days old with genetically confirmed SMA but no symptoms, all of whom received daily risdiplam treatment, demonstrating the potential of early intervention.

Researchers are also investigating prenatal administration of risdiplam, with early promising results, to further improve outcomes for SMA patients.

These findings underscore that early treatment can alter the disease course of SMA, highlighting the importance of neonatal screening and prompt therapy initiation.