A Phase 1/2 interventional study of autologous CD34-selected peripheral blood stem cells transplant and Alemtuzumab in Crohn's Disease, sponsored by Paul Szabolcs. Recruiting at 2 sites in United States. Open to participants aged 10 Years to 60 Years. Per ClinicalTrials.gov, last updated 2025-12-15.
Sponsored by Paul Szabolcs · Phase 1/2, Interventional, and Treatment
The objective of this study is to evaluate the safety and effectiveness of administering high-dose chemotherapy followed by infusion of autologous CD34-selected peripheral blood stem cells (PBSC) in pediatric and adult patients with severe Crohn's disease.
Crohn's disease is considered to be an immune-mediated disease of the intestinal tract, typically treated using immune modulating or immune suppressive therapies. These treatments include local anti-inflammatory agents such as 5 aminosalicylic acid products, broad immune suppression using corticosteroids, azathioprine, or methotrexate; cytokine suppression such as antibody against TNFα; IL-12 and antibiotics such as ciprofloxacin and metronidazole that work by decreasing the putative antigen exposure to the intestine. There is little in the literature available on mortality data related to Crohn's Disease, but one series by Farmer et al showed 6% mortality attributable to Crohn's disease. The mortality rate for selective patients with refractory and severe disease is probably higher.
This protocol is based on the premise that the sustained inflammation of the GI tract that is characteristic of Crohn's disease is the result of defective mucosal T cell tolerance. The mucosal tolerance is normally maintained by CD4 + T cells characterized as T helper 3 (Th3) and T regulatory 1 (TR1) T cell clones producing TGFβ and IL-10 respectively. There has been much speculation on a possible infectious etiology of IBD implicating primarily mycobacterial organisms, though despite extensive research no pathogenic organisms have definitively been identified. In genetic cytokine knockout animal models of IBD, the typical nonpathogenic enteric flora is sufficient to induce a chronic inflammatory reaction. Autoreactive T cells appear to have broken through the mucosal tolerance with characteristic T helper 1 cytokine profile secreting IL-1 and IFNγ.
In theory the most efficient approach to eradicate autoimmune T cell clones is through replacement of the defective immune system with hematopoietic stem cells (HSC) from a healthy allogeneic donor. However, the risks of morbidity and mortality associated with allogeneic HSC transplantation currently do not appear to be justified even in treatment of refractory cases of Crohn's disease. An alternative approach is to use autologous HSC from which potential autoreactive T-cells have been eliminated, based on the hypothesis that from the T-cell depleted autologous graft reconstitution of normal immunity will occur without regeneration of autoimmune clones. Pilot trials in Crohn's and other autoimmune diseases have confirmed the validity of this hypothesis. T-cells in the CD34 selected PBSC product are significantly depleted. If active disease recurs despite intensive immunoablation, it is likely that either CD34 selection did not adequately remove cells responsible for the autoreactive state, or that the emerging genetically predisposed immune system was re-exposed to autoantigens.
Unlike allogeneic transplants, the autologous transplant approach has greatly reduced morbidity and mortality due to the absence of graft rejection and graft versus host disease reactions. Currently, autologous HSCT demonstrate that transplant-related mortality is around 5% when transplanted for acute leukemia.
1,992 studies on the registry are indexed under Crohn Disease; 478 are open to participants now.
This study's planned enrollment of 20 is below the median of 67 across 1,260 interventional studies indexed under Crohn Disease.
Browse Crohn Disease studies →Paul Szabolcs is the lead sponsor of 9 studies on the registry; 9 are open to participants now.
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.
Examples of subjects for whom stem cell transplant therapy would be appropriate include, but are not limited to:
5.2 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.
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.
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
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 number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.
It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.
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.
From a breathing test (spirometry): how much air you can blow out in the first second. Often given as a percentage of what is expected for your age, height and sex.
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.
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 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.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
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.
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.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Absolute neutrophil count (ANC)
The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.
It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (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.
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.
FEV1
From a breathing test (spirometry): how much air you can blow out in the first second. Often given as a percentage of what is expected for your age, height and sex.
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.
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.
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.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
High-dose immunotherapy followed by infusion of autologous CD34-selected peripheral blood stem cells (PBSC)
Biological: autologous CD34-selected peripheral blood stem cells transplant · Drug: Alemtuzumab · Drug: ATG · Drug: Melphalan · Drug: Thiotepa · Drug: Rituximab · Drug: Cyclophosphamide · Drug: G-CSF · Drug: Mesna
high-dose immunotherapy followed by infusion of autologous CD34-selected peripheral blood stem cells (PBSC)
Transplant conditioning
Also known as: Campath-1H
Transplant conditioning
Also known as: Anti-thymocyte globulin, rabbit; Thymoglobulin
Transplant conditioning
Also known as: L-phenylalanine mustard, phenylalanine mustard, L-PAM, or L-sarcolysin
Transplant conditioning
Transplant conditioning
Also known as: Rituxan
Mobilization
Also known as: Cytoxan
Mobilization
Also known as: Neupogen, Granix, Zarxio, Filgrastim
Mobilization
Number of participants with regimen-related toxicities.
Time frame: From baseline to 24 months post bone marrow transplant
Number of participants with life-threatening infections.
Time frame: From baseline to 24 months post bone marrow transplant
Change and duration in the Harvey Bradshaw Index (HBI).
Time frame: Change from Baseline to 24 months post Bone Marrow Transplant
Change and duration in the Crohn's Disease Activity Index (CDAI).
Time frame: Change from Baseline to 24 months post Bone Marrow Transplant
Change and duration in the Pediatric Crohn's Disease Activity Index (PCDAI).
Time frame: Change from Baseline to 24 months post Bone Marrow Transplant
Number of days it takes for Absolute Neutrophil Count (ANC) to reach greater than 500.
Time frame: 3 consecutive days once ANC is greater than 500.
Number of days it takes for Platelet count to reach greater than 20,000/mm3
Time frame: From baseline to 24 months post Bone Marrow Transplant.
Number of days it takes for T cell Recovery
Time frame: 24 months post Bone Marrow Transplant
Number of participants who have long term cardiac complications
Time frame: 24 months post Bone Marrow Transplant
Number of participants who have long term endocrine complications
Time frame: 24 months post Bone Marrow Transplant
Number of participants with active advanced Crohn's disease who have immune dysregulation evolution and correction.
Time frame: From Baseline to 24 months post bone marrow transplant
Biomarker identification for relapse
Time frame: From baseline to 24 months post bone marrow transplant
Plan to share: No
No publications or documents are linked to this record.
Started Jun 2012 (actual). Primary completion is estimated for Dec 2026, 174 months after the start.
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.
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.
Paul Szabolcs