A Phase I clinical trial published in The Lancet has demonstrated that combining stem cell therapy with standard fetal surgery is both safe and promising for treating myelomeningocele, a severe form of spina bifida. Notably, surgeons used live stem cells directly on a fetus’s damaged spine for the first time, potentially improving outcomes beyond those achieved with conventional fetal surgery alone.
Understanding Spina Bifida and Current Limitations
Spina bifida is a congenital condition in which the spinal cord fails to develop properly, leaving part of it exposed. Consequently, affected children often face lifelong complications such as paralysis, difficulty walking, and bladder and bowel dysfunction.
Although doctors currently perform fetal surgery during pregnancy to close the spinal opening, the procedure does not always prevent long-term neurological damage. Therefore, researchers have sought innovative approaches to enhance nerve protection and recovery.
How the Stem Cell Procedure Works
In the trial, six pregnant women carrying fetuses diagnosed with spina bifida underwent standard fetal surgery. However, surgeons added a crucial step: they applied placenta-derived mesenchymal stem cells (PMSCs) directly onto the exposed spinal cord during the repair.
These stem cells, sourced from the placenta, reduce inflammation, promote tissue healing, and protect developing nerve cells. By delivering them directly to the site of injury, the surgical team aimed to strengthen spinal repair and improve neurological outcomes.
Encouraging Early Outcomes
As reported by medicalxpress, the six babies, born between July 2021 and December 2022, showed highly encouraging results. All spinal repairs remained intact at birth, and none of the infants developed infections, abnormal tissue growth, or tumor formation.
Importantly, post-birth MRI scans confirmed that hindbrain herniation—a brain abnormality commonly associated with spina bifida—reversed in every case. Furthermore, researchers observed no serious adverse effects linked to the stem cell therapy during the trial or subsequent follow-up.
Long-Term Monitoring Underway
Researchers will continue to monitor the children closely until they reach six years of age. Through regular medical assessments, the team will evaluate mobility, neurological development, overall health, and quality of life. This extended follow-up will help confirm the long-term safety and sustained benefits of the treatment.
Next Steps in Clinical Research
Meanwhile, larger and longer-term clinical trials are underway to refine surgical techniques and standardise treatment protocols. These studies aim to verify whether the therapy consistently improves birth outcomes, mobility, and long-term functioning.
Throughout the process, regulatory authorities are working closely with investigators to ensure rigorous safety and effectiveness standards.
A Milestone in In-Utero Therapy
Researchers believe this breakthrough marks a major milestone in the field of in-utero stem cell treatment for congenital disorders. If future trials confirm its benefits, the therapy could become a standard option for fetal repair of spina bifida.
Ultimately, this innovation offers renewed hope to families worldwide and may pave the way for applying stem cell techniques during fetal surgery to treat other birth defects.