The FDA approved AveXis’ Zolgensma (onasemnogene abeparvovec-xioi) as the first gene therapy approved to treat children less than two years of age with spinal muscular atrophy (SMA), a leading genetic cause of infant mortality.

Zolgensma is an adeno-associated virus vector-based gene therapy that targets the cause of SMA, a rare genetic disease caused by a mutation in the survival motor neuron 1 (SMN1) gene. Children with the condition have problems holding their head up, swallowing and breathing.

“Today’s approval marks another milestone in the transformational power of gene and cell therapies to treat a wide range of diseases,” said Acting FDA Commissioner Ned Sharpless.