A stem cell patch derived from donor placentas has successfully reversed a brain complication in fetuses diagnosed with the most severe form of spina bifida, according to results from a world-first clinical trial published in The Lancet.
The six-patient trial, led by Diana Farmer at the University of California, Davis, targeted myelomeningocele, a condition in which the spinal cord and surrounding tissue protrude through a gap in the vertebrae. It affects approximately 1 in every 2,800 births in the United States each year, frequently impairing mobility and bowel and bladder function.
How the Patch Works
All six fetuses enrolled in the trial had developed hindbrain herniation by around 24 weeks’ gestation. This complication occurs when excess fluid accumulates in the skull, forcing the cerebellum through the base of the skull. Standard in-utero surgery addresses this, but outcomes remain inconsistent.
In this trial, fetuses underwent the conventional surgical repair and also received a patch measuring a few centimetres long, containing stem cells embedded in a matrix of sticky proteins. Surgeons placed the patch directly on the spine before closing the skin over it. Farmer described the mechanism simply: “The cells secrete their magic stem cell juice.”
MRI scans after birth showed that hindbrain herniation had completely reversed in all six infants. Surgical sites healed without signs of abnormal cell growth, which Farmer identified as a primary concern before the trial began. “A key worry was that adding stem cells in a fetus would make the cells grow like crazy, but we didn’t see that,” she said.
One Family’s Outcome
The mother of one participant, a now 4-year-old boy named Toby, had expected her son would need a wheelchair after his diagnosis in the womb. “But Toby is healthy, has hit all of his milestones — he’s walking, running and jumping — and has no problems with bladder control, which is rare for people with the condition,” she said.
Bladder and bowel dysfunction affects the majority of people with myelomeningocele, making that particular outcome notable within the context of the trial results.
What the Current Evidence Shows
The existing standard of care involves tucking the spinal cord back into the vertebrae and sealing the skin during fetal surgery. Farmer has been direct about its limits: “Many children still end up unable to walk and there’s usually no improvement in bowel or bladder control.”
The stem cell patch appeared to match the standard treatment’s effectiveness on hindbrain herniation while potentially offering broader neurological benefits, though long-term walking outcomes have not yet been formally assessed in this cohort.
Panicos Shangaris at King’s College London, who was not part of the research team, expressed cautious optimism. “My personal opinion is that this will improve long-term outcomes compared to the standard approach, based on evidence from animal studies,” he said. Shangaris also noted that regulatory approval would most likely require a randomised head-to-head trial comparing both interventions directly, rather than benchmarking against a historical dataset.
The Road to a Larger Trial
The research team plans to expand to a 35-fetus trial, comparing outcomes from the stem cell patch against results from a previous study using conventional surgery alone. Farmer’s team sees this as the next step toward establishing whether the approach delivers durable improvements in mobility and quality of life.
The cause of spina bifida remains unknown, though folic acid deficiency during pregnancy is an established risk factor.
This article is a curated summary based on third-party sources. Source: Read the original article
