A Phase 2 interventional study of Anti-Thymocyte Globulin (Rabbit) and Fludarabine in Aplastic Anemia and Bone Marrow Failure Syndrome, sponsored by St. Jude Children's Research Hospital. Recruiting at 1 site in United States. Open to participants aged Up to 21 Years. Per ClinicalTrials.gov, last updated 2026-09-16.
Sponsored by St. Jude Children's Research Hospital · Phase 2, Interventional, and Treatment
This study is a prospective, single center phase II clinical trial in which patients with Severe Aplastic Anemia (SAA) ) will receive a haploidentical transplantation. The purpose of this study is to learn more about newer methods of transplanting blood forming cells donated by a family member that is not fully matched to the patient. This includes studying the effects of the chemotherapy, radiation, the transplanted cell product and additional white blood cell (lymphocyte) infusions on the patient's body, disease and overall survival. The primary objective is to assess the rate of engraftment at 30 days and overall survival (OS) and event free survival (EFS) at 1 year post-hematopoietic cell transplantation (HCT).
Primary Objectives
Secondary Objectives
Exploratory Objectives
Immunosuppressant therapy (IST) is the main treatment for SAA for patients who do not have an HLA-matched sibling donor available for transplant. But some patients with SAA do not respond to IST and some others relapse after IST. HCT using an unrelated but HLA-matched donor is the only curative option for these patients but many patients lack a suitable HLA-matched donor. St Jude is trying to increase donor options for these patients by using novel therapeutic strategies by combining two widely used of GVHD prophylaxis methods: i) selective T cell depletion and ii) use of post-transplant cyclophosphamide. This will allow expansion of the donor pool to include haploidentical donors as well as reduce the risk of GVHD. The goal of this protocol is to test whether combining these GVHD prophylaxis approaches will allow use of haploidentical donors, reduce risk of GVHD, reduce transfusion dependence and improve immune reconstitution.
For this study chemotherapy, antibodies and radiation will be given to prepare the body to receive donor cells. Participants will then be given the donor cell infusion.
Patients will receive two types of donor blood cell products - a progenitor blood cell infusion and then a donor lymphocyte infusion. Both the progenitor blood cell and the donor lymphocyte infusion will be processed in a laboratory at St. Jude using a machine called the CliniMACS™.
In this clinical trial, participants will receive a special type of progenitor blood cells (called TCRαβ- depleted blood cells) from the donor.
After the donor progenitor cells have started to grow within the body (engraftment), participants will receive a second product that contains mature immune cells. These immune cells called CD45RA-depleted lymphocytes or donor lymphocyte infusion (DLI) will help fight infections in the body after the transplant and strengthen the developing immune system.
371 studies on the registry are indexed under Anemia, Aplastic; 98 are open to participants now.
This study's planned enrollment of 21 is below the median of 37 across 281 interventional studies indexed under Anemia, Aplastic.
Browse Anemia, Aplastic studies →St. Jude Children's Research Hospital is the lead sponsor of 440 studies on the registry; 102 are open to participants now.
Of its 61 completed or terminated interventional studies of FDA-regulated products, 37 (61%) have results posted.
Counted across the registry records on this site, refreshed daily.
Inclusion Criteria for Transplant Recipient
Confirmed diagnosis of SAA or a single lineage cytopenia
(a) SAA or single lineage cytopenia will be defined as follows:
Adequate organ function defined as:
Exclusion Criteria for Transplant Recipient:
Inclusion Criteria for Haploidentical Donor
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
A line of therapy is one course of treatment, which may combine several drugs. First-line is the first course given; second-line follows when that stops working or is not tolerated.
“Two prior lines” means two courses that count separately under the study’s rules — not simply two drugs. Ask the study team if you are unsure how yours are counted.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
A 0–100 scale of how well someone can carry out everyday activities. 100 is no complaints and no signs of illness; 70 is able to look after yourself but not to work or keep up normal activity; 50 is needing considerable help and frequent medical care.
Studies often ask for 60 or 70 and above. Your doctor gives the score.
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Relapsed and refractory
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Line of therapy
A line of therapy is one course of treatment, which may combine several drugs. First-line is the first course given; second-line follows when that stops working or is not tolerated.
“Two prior lines” means two courses that count separately under the study’s rules — not simply two drugs. Ask the study team if you are unsure how yours are counted.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
LVEF (left ventricular ejection fraction)
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Creatinine clearance (CrCl)
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Karnofsky performance status (KPS)
A 0–100 scale of how well someone can carry out everyday activities. 100 is no complaints and no signs of illness; 70 is able to look after yourself but not to work or keep up normal activity; 50 is needing considerable help and frequent medical care.
Studies often ask for 60 or 70 and above. Your doctor gives the score.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Bilirubin
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Allogeneic and autologous transplant
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
To assess the safety and efficacy of haploidentical donor transplantation for patients with severe aplastic anemia who lack an available HLA-matched donor. The goal of this study is to develop a novel, reduced-toxicity, post-transplant pharmacologic immunosuppression (GVHD prophylaxis)- free, highly tolerogenic haploidentical transplant regimen that is associated with few post- transplant complications or late toxicities and is available promptly to all patients, irrespective of matched donor availability. Cells for infusion are prepared using the CliniMACS System.
Drug: Anti-Thymocyte Globulin (Rabbit) · Drug: Fludarabine · Drug: Cyclophosphamide · Drug: Mesna · Drug: G-CSF · Radiation: Total Lymphoid Irradiation (TLI) · Device: CliniMACS · Biological: HPC, A Infusion · Biological: CD45RA-depleted DLI
Given intravenously (IV)
Also known as: thymoglobulin, rabbit ATG
Given intravenously (IV)
Also known as: Fludara Flu Dara
Given intravenously (IV)
Also known as: CYTOXAN
Given intravenously (IV)
Also known as: MESNEX
Filgrastim is a human granulocyte colony-stimulating factor (G-CSF), produced by recombinant DNA technology. Dosage and Route of Administration: 5mcg/kg subcutaneous or intravenous daily until ANC \>2000 for 2 consecutive days, or as clinically indicated
Also known as: Neupogen, Filgrastim
TLI will be given at 800 cGy total dose in 4 fractions.
Also known as: TLI
The mechanism of action of the CliniMACS Cell Selection System is based on magnetic-activated cell sorting (MACS). The CliniMACS device is a powerful tool for the isolation of many cell types from heterogeneous cell mixtures, (e.g. apheresis products). These can then be separated in a magnetic field using an immunomagnetic label specific for the cell type of interest, such as CD3+ human T cells.
Also known as: Cell Selection System
Given intravenously Day 0-HPC, A Infusion (TCR αβ+/CD19+-depleted graft)
CD45RA-depleted DLI will be given at least ONE week after engraftment
Engraftment
Rate of patients engrafting at day 30 after TCR αβ+ T-cell-depleted graft infusion in patients receiving a single dose of post graft infusion cyclophosphamide.
Time frame: 30 days
Overall and event free survival
Rate of overall survival and event free survival at 1-year post transplantation.
Time frame: 1 year
Graft vs host disease
Incidence of acute and chronic GVHD after hematopoietic cell transplant
Time frame: 1 year
Graft rejection
Rate of secondary graft rejection at 1-year post transplantation
Time frame: 1 year
Viral reactivation
Cumulative incidence of viral reactivation post-transplant (CMV, EBV and adenovirus)
Time frame: 1 year
Immune reconstitution
We will record immune reconstitution parameters, including the order and magnitude of recovery of the different subtypes of leukocytes. Results will be summarized by descriptive statistics. The pattern of immune reconstitution will be evaluated using longitudinal approaches such as mixed effect models or generalized estimating equation (GEE) approach.
Time frame: 1 year
Plan to share: Yes — Individual participant de-identified datasets containing the variables analyzed in the published article will be made available (related to the study primary or secondary objectives contained in the publication). Supporting documents such as the protocol, statistical analyses plan, and informed consent are available through the CTG website for the specific study. Data used to generate the published article will be made available at the time of article publication. Investigators who seek access to individual level de-identified data will contact the computing team in the Department of Biostatistics (ClinTrialDataRequest@stjude.org) who will respond to the data request.
Supporting information: Study protocol, Statistical analysis plan, Informed consent form
Time frame: Data will be made available at the time of article publication.
Access criteria: Data will be provided to researchers following a formal request with the following information: full name of requestor, affiliation, data set requested, and timing of when data is needed. As an informational point, the lead statistician and study principal investigator will be informed that primary results datasets have been requested.
Started Jan 2021 (actual). Primary completion is estimated for Jul 2029, 101 months after the start.
Of 52 non-industry phase 2 interventional studies under Anemia, Aplastic, half reached primary completion within 93 months of starting (the median), counting those still running; a quarter within 55 and three quarters within 111. This study's planned 101 months is close to that.
Counting every sponsor, half of 60 studies reached it within 76 months; a quarter within 39 and three quarters within 104.
How these figures are worked out, and which studies are left out of them.
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.
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Studies of the drugs tested here: Thymoglobulin · Fludarabine · Cyclophosphamide · Mesna · Granulocyte Colony-Stimulating Factor
St. Jude Children's Research Hospital →