Prenatal Transplantation for Fetuses With Fanconi Anemia

February 16, 2026 updated by: Agnieszka Czechowicz

A Phase I/II, Non-Randomized Study of the Safety and Efficacy of In Utero Hematopoietic Stem Cell Transplantation for the Treatment of Fanconi Anemia in Affected Fetuses

The investigators aim to evaluate the safety and efficacy of in utero hematopoietic stem cell transplantation (IUHSCT) for the treatment of fetuses diagnosed with Fanconi anemia (FA) during pregnancy.

Study Overview

Detailed Description

Fanconi Anemia (FA) is a genetic disorder known to shorten the lifespans of those diagnosed due to inherited chromosomal fragility that leads to hematopoietic failure (cytopenia, aplastic anemia, myelodysplasia, or leukemia), increased cancer risk, and other possible rare organ dysfunction such as congenital structural anomalies. Importantly, 80-90% of FA patients develop bone marrow failure (BMF) by 12 years of age.

This is a phase I/II clinical trial to investigate the safety and efficacy of performing in utero hematopoietic stem cell transplantation (IUHSCT) for fetuses diagnosed with FA during pregnancy. The investigators aim to recruit twelve participants with a prenatal diagnosis of FA. Participants will undergo bone marrow harvest followed by an ultrasound guided in utero infusion of maternal stem cells. Transplanting maternal cells into the fetus takes advantage of the immature fetal immune system and existing maternal-fetal tolerance during pregnancy to enable stem transplantation without use of any conditioning or immunosuppression.

The investigators intend to demonstrate that it is safe and effective to perform IUHSCT in fetuses diagnosed with FA. Additionally, the investigators want to demonstrate postnatal chimerism of maternal cells and correction of the DNA-repair deficiency in the blood and bone marrow. This procedure hopes to prevent the need for a future bone marrow transplant later in life, or if one remains necessary then it hopes that conditioning and immune suppression will not be required when using maternal stem cells due to persistant maternal tolerance.

Study Type

Interventional

Enrollment (Estimated)

12

Phase

  • Phase 2
  • Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

    • California
      • San Francisco, California, United States, 94143
        • University of California, San Francisco
      • Stanford, California, United States, 94305
        • Stanford University

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child
  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Male or female fetuses from 19^0/7 - 28^0/7 weeks gestational age at time of transplant.
  • Diagnosed with FA by either chorionic villus sampling (CVS), or amniocentesis, or cordocentesis with abnormal fetal chromosomal breakage studies and/or FANC gene mutations when combined with at least one of the following: 1) abnormal chromosomal breakage result consistent with an FA diagnosis, 2) family history of a 1st degree relative with confirmed FA, or 3) congenital anomalies consistent with the diagnosis of FA on fetal ultrasound.
  • Parents must consent to fetal autopsy in the event of a fetal demise.
  • Adequate bone marrow harvest from maternal participant is a condition for inclusion.

Exclusion Criteria:

  • Fetal Participant Exclusion Criteria: Major anatomic or genetic anomalies that contributes a significant morbidity or mortality risk, and/or echocardiogram or ultrasound findings that indicate a high risk of fetal demise after fetal intervention. Fetuses with a normal chromosomal breakage study that determines they are likely FA negative.
  • Maternal Subject Exclusion Criteria: Maternal participants will be excluded if they have one or more morbidities that would preclude bone marrow harvest and fetal intervention including, but not limited to, morbid obesity with a body mass index greater than 40, significant maternal cardiac disease, mirror syndrome, clinically symptomatic maternal anemia, Preterm premature rupture of membranes (PPROM), Active Preterm labor (PTL), opioid use disorder, current use of anticoagulants.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Intervention - in utero hematopoietic stem cell transplantation
Single dose in utero hematopoietic stem cell transplantation (IUHSCT) in fetuses with Fanconi anemia during 19 - 28 weeks gestation. The cellular product is: Semi-allogeneic, Related, Maternal Bone Marrow-Derived, Miltenyi CliniMACS Plus enriched CD34+ hematopoietic stem cells administered in utero at a dose of 1 x 10^7-10^9 cells/kg fetal weight with equal to or less than 1% CD3+ T cells (equivalent to 10^5-10^7 T cells/kg fetal weight) in a final volume of 2-5ml suspended in 5% human serum albumin in Normosol buffer (Hospira, Inc.).
Single-dose IUHSCT Administration of Semi-allogeneic, Related, Maternal Bone Marrow-Derived, Miltenyi CliniMACS Plus Enriched CD34+ Hematopoietic Stem Cells Administered in Utero via fetal injection during 19 - 28 weeks gestation.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Number of Maternal Participants with Treatment-Emergent Adverse Events (TEAEs) as Assessed by CTCAE v6.0.
Time Frame: From day of treatment to final maternal study visit (30 +/- 15 days after delivery).
Number of maternal participants with treatment-emergent adverse events (TEAEs) as assessed by CTCAE v6.0.
From day of treatment to final maternal study visit (30 +/- 15 days after delivery).
Number of Maternal Participants with Serious Adverse Events (SAEs) as Assessed by CTCAE v6.0.
Time Frame: From day of treatment to final maternal study visit (30 +/- 15 days after delivery).
Number of maternal participants with serious adverse events (SAEs) as assessed by CTCAE v6.0.
From day of treatment to final maternal study visit (30 +/- 15 days after delivery).
Number of Fetal Participants with Treatment-Emergent Adverse Events (TEAEs) as Assessed by CTCAE v6.0.
Time Frame: From day of treatment to child's final study visit (24 months after birth).
Number of fetal participants with treatment-emergent adverse events (TEAEs) as assessed by CTCAE v6.0.
From day of treatment to child's final study visit (24 months after birth).
Number of Fetal Participants with Serious Adverse Events (SAEs) as Assessed by CTCAE v6.0.
Time Frame: From day of treatment to child's final study visit (24 months after birth).
Number of fetal participants with serious adverse events (SAEs) as assessed by CTCAE v6.0.
From day of treatment to child's final study visit (24 months after birth).

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Tippi MacKenzie, MD, University of California, San Francisco
  • Principal Investigator: Yair Blumenfeld, MD, Stanford University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

July 1, 2026

Primary Completion (Estimated)

July 1, 2030

Study Completion (Estimated)

July 1, 2032

Study Registration Dates

First Submitted

February 6, 2026

First Submitted That Met QC Criteria

February 6, 2026

First Posted (Actual)

February 13, 2026

Study Record Updates

Last Update Posted (Actual)

February 19, 2026

Last Update Submitted That Met QC Criteria

February 16, 2026

Last Verified

February 1, 2026

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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