A first-in-human CuRE trial tested placenta-derived mesenchymal stem cells seeded onto an FDA-approved extracellular matrix and applied to the exposed spinal cord during standard open fetal surgery for myelomeningocele, a severe form of spina bifida.

The US study found that delivering these placenta-derived cells during in utero repair is safe and may improve mobility and quality of life after birth, based on six delivered babies.

The cells were delivered in conjunction with standard fetal surgery and did not disrupt the surgical workflow or immediate neonatal outcomes.

MRI after birth showed reversal of hindbrain herniation in all treated infants, and no tumor formation or tissue abnormalities were observed at birth.

All six pregnancies resulted in intact spinal repairs and healthy newborns, with follow-up indicating better-than-expected functional indicators compared with typical surgical outcomes.

The trial enrolled six fetuses between 24 and 26 weeks gestation in 2021–2022, with deliveries around 35 weeks via cesarean section, and results published in The Lancet.

The stem-cell patch was embedded in a matrix and applied to the exposed spinal cord alongside standard fetal repair, aiming to promote spinal tissue growth and address neural damage beyond surgery alone.

Researchers say this platform demonstrates scalable, clinically feasible targeted fetal delivery of biologics, potentially altering lifelong health trajectories by reducing disability and its social and economic impacts.

No safety concerns such as tumours, wound-healing issues, or interference with hindbrain development were observed in this small cohort.

Current in utero surgery improves outcomes but leaves a substantial proportion of children unable to walk independently, underscoring the need for therapies addressing neural damage.

The study is framed around the two-hit hypothesis, combining neuroprotection with prenatal repair to mitigate ongoing neural injury.

Independent experts cautioned that larger studies are needed, but the results are viewed as a potential milestone that could redefine fetal surgery and neurological protection for spina bifida.