A Phase 1 interventional study of Hematopoietic stem cell transplantation in Sickle Cell Disease, sponsored by City of Hope Medical Center. Withdrawn. Open to participants aged 1 Year to 30 Years. Per ClinicalTrials.gov, last updated 2026-10-26.
Sponsored by City of Hope Medical Center · Phase 1, Interventional, and Treatment
Closed to accrual - no accruals in CTMS
This is a study to evaluate the safety and toxicity of a treatment regimen consisting of 2 cycles of pre-transplant immunosuppressive therapy followed by myeloablative preparative regimen and allogeneic hematopoietic stem cell transplantation from a haploidentical donor in patients with sickle cell disease.
The overall goal of this study is to expand the donor pool for hematopoietic stem cell transplantation in sickle cell disease using haploidentical donors, and to develop a non-toxic, myeloablative regimen, with the goal of achieving a consistent donor chimerism utilizing pre-transplant immunosuppressive therapy.
All patients will receive an haploidentical hematopoietic stem cell transplant with the following conditioning and GvHD prevention:
Pre-transplant immunosuppressive therapy:
2 cycles of Fludarabine and Dexamethasone x 5 days each cycle
Conditioning regimen:
rATG daily x 3 days, Fludarabine daily x 6 days and Busulfan daily x 4 days
GVHD prophylaxis:
Cyclophosphamide day +3 and +4, Tacrolimus and Mycophenolate mofetil
1,134 studies on the registry are indexed under Anemia, Sickle Cell; 238 are open to participants now.
Browse Anemia, Sickle Cell studies →City of Hope Medical Center is the lead sponsor of 677 studies on the registry; 181 are open to participants now.
Of its 31 completed or terminated interventional studies of FDA-regulated products, 12 (39%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion criteria:
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.
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).
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.
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.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
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.
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
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.
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.
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.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
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.
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.
Biological: Hematopoietic stem cell transplantation
Haploidentical stem cell transplantation with pre-transplant immunosuppressive therapy
Rate of unacceptable adverse events that are defined as any of the following events that occur from start of pre-transplant immunosuppressive therapy to the first 100 days post HCT:
* Rate of death of any causes * Rate of study discontinuation or early withdrawal * Rate of graft failure • Primary graft failure is defined as failure to achieve a neutrophil count of 0.5 x 109/L before day +42 or mixed chimerism with failure to achieve \<30% Hgb S on electrophoresis after day +180. Secondary graft failure is defined as recovery followed by a sustained loss of initial graft. * Rate of grade 4 non-hematological toxicities per NCI CTCAE v4.03 that last more than 21 days
Time frame: 190 days
Time to donor neutrophil engraftment
Day of Neutrophil Engraftment: The first of three consecutive days on which the ANC is ≥0.5x109/L
Time frame: 24 months
Time to donor platelets engraftment
Day of Platelet engraftment: The first documented day on which the platelet count is \>20x109/L unsupported by platelet transfusions for 7 days
Time frame: 24 months
Rate of graft failure
Primary graft failure is defined as failure to achieve a neutrophil count of 0.5 x 109/L before day +42 or mixed chimerism with failure to achieve \<30% Hgb S on electrophoresis after day +180. Secondary graft failure is defined as recovery followed by a sustained loss of initial graft.
Time frame: 24 months
Incidence of acute GvHD (grade II - IV) during the first 100 days after transplantation
Time frame: 100 days after transplantation
Incidence of chronic GvHD
Time frame: 24 months
Overall survival rate
• Overall survival: the time from start of PTIS to death, or last follow-up, whichever comes first.
Time frame: 24 months
Event-free survival rate
• Event-free survival: the time from start of PTIS to death, the unacceptable events, or last follow-up, whichever comes first.
Time frame: 24 months
Disease free survival rate
• Disease free survival: the time from HCT to death, secondary graft failure, or last follow-up, whichever comes first.
Time frame: 24 months
Immune reconstitution at day 100, 180 and 365
• Immune reconstitution: measurement of CD3, CD4, CD8, CD11b, CD14, CD56, CD20/19, FoxP3+ Treg, and memory subsets.
Time frame: 24 months
Number of Participants With Treatment-Related Adverse Events as Assessed by CTCAE v4.0 from start of pre-transplant immunosuppressive therapy to 24 months post transplant
Time frame: 24 months post-transplant
Percent of donor chimerism at 12 and 24 months after HCT
Time frame: 12 and 24 months after HCT
Change From Baseline in Pain Scores using Numerical Rating Scale or Faces Pain Rating Scale at 100 days, 6 months and 12 months post-transplant
Time frame: 100 days, 6 months and 12 months post-transplant
No study locations are listed for this record.
Start is estimated for Feb 2018; primary completion for Jan 2027, 107 months later.
How these figures are worked out, and which studies are left out of them.
Closed to accrual - no accruals in CTMS
Closed to accrual - no accruals in CTMS
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is withdrawn, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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