A Phase 1/2 interventional study of Placental Mesenchymal Stem Cells seeded on a commercially available dural graft extracellular matrix and Untreated contemporaneous cohort in Myelomeningocele, sponsored by University of California, Davis. Recruiting at 1 site in United States. Open to participants aged 19 Weeks to 25 Weeks. Per ClinicalTrials.gov, last updated 2026-01-20.
Sponsored by University of California, Davis · Phase 1/2, Interventional, and Treatment
Spina bifida, or myelomeningocele (MMC), is a birth defect that results in paralysis, excess fluid on the brain (hydrocephalus), and impaired ability to urinate and have bowel movements normally. In a previous study (the MOMS trial), surgery before birth (in-utero/fetal surgery) was shown to reduce the need for shunting for hydrocephalus. There was also some improvement in ambulation, but 58 % of the children still could not walk unassisted.
This study is testing living stem cells from placenta added to the fetal repair in an effort to improve the ability to walk. Previous animal studies have shown dramatic improvement in walking and bowel and bladder function when placental stem cells are added to MMC repair. Use of these "living" cells may protect the developing spinal cord, prevent further injury, and may even reverse existing damage to the nerves that control movement. This study is assessing the safety and efficacy of adding stem cells to open fetal surgery for MMC in humans.
Historically, treatment of MMC was limited to post-natal surgery to close the dura and skin over the spinal cord to prevent meningitis, which had no effect on motor function. The potential benefit of earlier intervention was realized when prenatal ultrasound of patients with MMC early in gestation revealed near-normal leg movements despite displaying paralysis at birth. This finding gave credence to the two-hit hypothesis that paralysis was progressive during prenatal life and suggested that fetal intervention could prevent the secondary damage to the spinal cord. Fetal repair of MMC did confer improvement in motor function of children treated in the Management of Myelomeningocele (MOMS) randomized controlled trial. The promising results of the MOMS trial demonstrated the potential for improvement of paralysis for these patients, but distal motor function still remained severely impaired in the majority of patients with MMC with standard in utero repair alone. While this demonstrated that the ideal time to intervene to prevent paralysis is in utero with the goal of preventing the accrual of ongoing damage to the spinal cord, there is still room for improvement. The remarkable regenerative capacity of the fetal environment combined with regenerative capacity of placental mesenchymal stem cells offers potential for augmentation of the fetal repair of MMC with a novel therapy to further reduce and repair the sustained spinal cord damage.
56 studies on the registry are indexed under Meningomyelocele; 14 are open to participants now.
This study's planned enrollment of 55 is above the median of 35 across 39 interventional studies indexed under Meningomyelocele.
Browse Meningomyelocele studies →University of California, Davis is the lead sponsor of 798 studies on the registry; 146 are open to participants now.
Of its 65 completed or terminated interventional studies of FDA-regulated products, 43 (66%) have results posted.
Counted across the registry records on this site, refreshed daily.
Eligibility for fetal surgery per the MOMS trial, which are:
Exclusion Criteria:
Not being eligible for fetal surgery per the MOMS trial, which includes:
One-time administration of PMSC-ECM during the course of in utero fetal myelomeningocele surgery will be administered
Biological: Placental Mesenchymal Stem Cells seeded on a commercially available dural graft extracellular matrix
Contemporaneous cohort of patients undergoing routine fetal or postnatal MMC repair without PMSC-ECM (non-PMSC untreated contemporaneous cohort).
Other: Untreated contemporaneous cohort
As in the current standard fetal surgery, under sonographic guidance, initial uterine entry will be accomplished by uterine stapling device or similar. The fetus will be given an intramuscular injection of pain medications and paralytic. The myelomeningocele will be closed in a standardized manner under magnification. As in the standard fetal operation, the spinal cord will be dissected from surrounding tissue and allowed to drop into the spinal canal. The PMSC-ECM product will then be tailored to the size of the spinal cord and applied topically, cell side down. The PMSC-ECM product will be sutured in place to the dura. Finally, the fetal skin will be closed in the standard fashion. The amniotic fluid volume will be replaced and antibiotics will be added. The uterus will be closed. The abdominal fascial layer and skin will be closed in routine fashion.
Also known as: PMSC-ECM
The addition of a non-PMSC treated cohort, the untreated contemporaneous cohort, has been added at the request of the FDA to provide contemporaneous patients for validation of the continued relevance of use of the outcomes of the MOMS trial as the comparison arm for the Phase 2a portion of the study.
Also known as: non-PMSC-ECM
Safety of the placenta-derived mesenchymal stem cell (PMSC-ECM) Product
Will be assessed by evaluating the presence or absence of cerebrospinal fluid leak, infection at the MMC repair site, failure of the MMC repair site to heal, and any unexpected growths or tumor formation. These will be assessed at birth by physical exam, brain and spinal ultrasound , and brain and spinal MRI.
Time frame: Assessed at birth
Efficacy of the PMSC-ECM Product
This is primarily evaluated by improvement in motor function 2 or more levels greater than expected by anatomic level of the defect and by patients' ability to walk independently. Bowel function will be assessed by caregiver questionnaires on bowel habits, and by anorectal manometry. Urologic function will be assessed by caregiver questionnaires regarding urologic function, by renal and bladder ultrasounds to evaluate for hydronephrosis and bladder abnormalities, and by video urodynamics.
Time frame: 30 months.
Plan to share: No
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
University of California, Davis