Giving stem cells to unborn babies diagnosed with spina bifida while they have in utero surgery could be “a major milestone” in the treatment of birth defects, doctors say.
A trial in the US found that applying stem cells from the mother’s placenta to her baby’s spine while it was being repaired was safe and improved the child’s mobility and quality of life.
Dr Diana Farmer, who led the study, said it was “conceivable” that the experimental therapy could become the usual way that spina bifida is treated before babies are born.
“If it makes more children able to walk who wouldn’t have then it would become their standard of care,” she said. “The results are super exciting and pave the way for lots of potential new treatments for spina bifida and other birth defects.”
The trial, reported in the Lancet on Friday, took place in 2021 and 2022 and involved six unborn babies with myelomeningocele, the “open” – more serious – form of spina bifida.
Surgeons at the Davis school of medicine at the University of California applied placenta-derived mesenchymal stem cells on to the exposed spinal cord of the babies, who were at 24 to 25 weeks of gestation at the time.
MRI scans after their birth confirmed that hindbrain herniation – brain abnormalities associated with spina bifida, in which the lower part of the brain slips into the neck area – was reversed in all six.
The stem cells did not cause tumours, interfere with the wound healing or prevent hindbrain herniation being reversed – all side-effects the researchers were aware could occur.
Kate Steele, the chief executive of the charity Shine, said the results were “very exciting”.
“The advances in stem cell science that have enabled this first-in-human trial to be possible are remarkable and we are delighted … that the safety of the procedure has been demonstrated,” she said.
“Having seen the difference foetal surgical repair is already making to the lives of children with myelomeningocele, and knowing that adding stem cell therapy to these established surgery techniques might one day improve outcomes for babies born with spina bifida, is very encouraging and very exciting.
“Improvements in bladder and bowel function will be particularly welcome.”
The Lancet published a linked comment piece about the findings by Dr Magdalena Sanz Cortes, a foetal medicine expert in Texas who was not involved in the trial.
If further studies confirmed its apparent benefits then “such results would herald a new era in foetal surgery and potentially lead the way to improving and reversing the neurological damage seen in utero in spina bifida”, she said.
Between 8,100 and 11,900 people in England and Wales are believed to live with open spina bifida. Shine said that an estimated 536 pregnancies a year involve the condition.
