Mobilization of CD34+ Peripheral Blood Stem Cells in Patients With Diamond Blackfan Anemia Syndrome (DBAS)

April 23, 2026 updated by: Alexandra Satty, Northwell Health

Mobilization of CD34+ Peripheral Blood Stem Cells With Filgrastim (Granulocyte-colony Stimulating Factor) and Plerixafor From Patients With Diamond Blackfan Anemia Syndrome

Gene therapy is a new possible treatment for the anemia of DBAS. Gene therapy will soon be available for patients with RPS19-mutated DBAS. This involves inserting the corrected RPS19 gene into the cells, leading to correction of the anemia. The application of gene therapy requires sufficient numbers of stem cells on which the correction can be performed. Stem cells must be mobilized (stimulated to move) from the bone marrow to the peripheral blood and then collected (also called 'harvested'). It is not known if patients with DBAS can mobilize enough stem cells into the peripheral blood to allow for the harvesting of sufficient numbers to permit genetic manipulation. It is important to demonstrate the ability to harvest an adequate number of stem cells before gene therapy can be tried in patients with DBAS. The purpose of this study is to determine if mobilization of stem cells from the bone marrow in patients with DBAS is enough to obtain the numbers of peripheral blood stem cells necessary for effective gene therapy. An actual harvest will not be done.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Diamond Blackfan anemia syndrome (DBAS) is a rare, inherited bone marrow failure syndrome, characterized by severe anemia, birth defects and a predisposition to cancer. The majority of patients with DBAS have a mutation in a gene encoding either a small (S) or large (L) subunit-associated ribosomal protein (RP). DBAS typically presents with severe anemia within the first two months of life. Approximately 80% of patients are initially responsive to corticosteroids with an improvement of their anemia, whereas 20% will not respond and will require red blood cell transfusions. Of the 80% of patients that initially respond to corticosteroid treatment, only about half of them will sustain a therapeutic response at a tolerable dose and the remainder will have to resort to transfusions for life. Overall ~20% of the patients may ultimately be able to discontinue corticosteroid or transfusion therapy and enter a treatment-independent phase. The only curative therapy for the anemia associated with DBAS at this time is allogeneic hematopoietic stem cell transplantation, however, this is limited by the availability of matched donors as well as the potentially life-threatening complications associated with transplantation.

There is a critical need for novel therapeutic options for these patients. Of the 28 known DBAS genes, RPS19 mutations are noted in 25% of patients. Gene therapy represents a potential curative option for the anemia of DBAS. This therapy involves inserting the corrected vector (in this case containing the RPS19 gene) into hematopoietic stem cells (HSCs), leading to correction of the anemia in animal models and, potentially, in humans. The application of gene therapy requires sufficient numbers of HSCs on which the correction can be performed. It has not been determined if patients with DBAS can mobilize enough HSCs into the peripheral blood to allow for the harvesting of sufficient numbers to permit genetic manipulation. It is important to demonstrate the ability to harvest an adequate number of HSCs before gene therapy can be contemplated for this rare population.

Patients with DBAS are known to have a reduced number of cells in the bone marrow, especially as the patients age, which raises the concern that HSCs may not be able to be mobilized into the peripheral blood. The goal of this project is to determine the feasibility of peripheral blood HSC collection in patients with DBAS to obtain the numbers necessary for effective gene therapy. Participants in this study will undergo bone marrow aspiration and biopsy to assess the cellularity and CD34+ cell count of the bone marrow, then begin a standard stem cell mobilization protocol consisting of filgrastim (granulocyte-colony stimulating factor, G-CSF; a white blood cell stimulating factor) and plerixafor. Participants will then undergo bloodwork by venipuncture to quantify the stem cell count in the peripheral blood to determine if enough stem cells can be collected. There will NOT be an actual stem cell collection. The study will also assess factors that may be predictive of successful peripheral blood HSC mobilization, including peripheral blood stem cell count, initial bone marrow cell number, and initial bone marrow CD34 count. The target population for this study will include individuals with a known DBAS mutation who are red blood cell transfusion dependent. The study aims to recruit a total of 10 participants between the ages of 3 and 30 years. At least 4 participants will be recruited with an RPS19 mutation and at least 6 participants will be under 18 years of age.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Observational

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
10

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

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

Study Locations

  • United States
    • New York
      • New Hyde Park, New York, United States, 11040
        • Recruiting
        • Cohen Children's Medical Center
        • Contact:
        • Contact:
        • Principal Investigator:
          • Alexandra Satty, MD

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

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Child
  • Adult

Accepts Healthy Volunteers

No

Sampling Method

Non-Probability Sample

Study Population

Patients with Diamond Blackfan Anemia Syndrome (DBAS) ages 3-30 with red blood cell transfusion dependence

Description

Inclusion Criteria:

  1. Diamond Blackfan anemia syndrome as defined by the known criteria with a known gene mutation
  2. Male or female patients of all ethnic background, greater than or equal to 3 years of age and weighing at least 10 kg, and less than or equal to 30 years of age
  3. Enrolled in Diamond Blackfan Anemia Registry of North America (DBAR)
  4. Chronically red blood cell transfusion dependent for at least 6 months
  5. Performance scale (Lansky Play-performance Scale for Pediatric Functional Status for age <16 years; Karnofsky Performance Scale for age ≥16 years) ≥ 70
  6. Must sign informed consent

Exclusion Criteria:

  1. Receiving prednisone therapy for treatment of DBAS (this does not include patients receiving physiologic steroid replacement for adrenal insufficiency)
  2. Known history of myelodysplasia or presence of a hematopoietic clone
  3. Current malignancy or previous treatment for malignancy
  4. Pregnancy or breast-feeding mother
  5. Known history of severe iron overload as defined by a liver iron concentration (LIC) > 15 mg Fe/ g dry liver weight

  6. Significant cytopenias, defined as:

    • Platelet count <100,000/mcL
    • Absolute neutrophil count <750/mCL
  7. Any GCSF use in the 3 months prior to enrollment
  8. Liver dysfunction: aspartate aminotransferase (AST), alanine aminotransferase (ALT), or direct bilirubin values >3 x the upper limit of normal (ULN)
  9. Kidney dysfunction: baseline estimated glomerular filtration rate (GFR) <70 mL/min/1.73 m2

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

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Feasibility of collecting 5-30 CD34+ cells/µL in patients ages 3 to 30 years with Diamond Blackfan anemia syndrome
Time Frame: 2 weeks
This study will analyze the number of participants that successfully achieve 5-30 CD34+ cells/µL peripheral blood during the study period.
2 weeks

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Time to successful mobilization of CD34+ cells/µL peripheral blood
Time Frame: 2 weeks
For participants who achieve a peripheral blood CD34+ count of 5-30/µL, the time (in days) from the start of mobilization regimen to successful mobilization (the day at which peripheral blood CD34+ count = 5-30/µL) will be quantified
2 weeks
Correlation of bone marrow CD34+ count with the ability to mobilize an adequate number of CD34+ cells in the peripheral blood.
Time Frame: 2 weeks
2 weeks
Correlation of mobilization of 5-30 CD34+ cells/µL peripheral blood with subject's age
Time Frame: 2 weeks
2 weeks
Correlation of mobilization of 5-30 CD34+ cells/µL peripheral blood with bone marrow cellularity.
Time Frame: 2 weeks
2 weeks
Correlation of mobilization of 5-30 CD34+ cells/µL peripheral blood with DBAS genotype
Time Frame: 2 weeks
2 weeks

Collaborators and Investigators

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

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Northwell Health

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Alexandra Satty, MD, Northwell Health

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)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
June 1, 2026

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
October 1, 2026

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
April 1, 2027

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
September 8, 2025

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
September 15, 2025

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
September 22, 2025

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
April 27, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
April 23, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
April 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 24-0953-CCMC

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

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

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.

Clinical Trials on Diamond Blackfan Anemia

Clinical Trials on Mobilization Regimen

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings