Stem Cell TransplantEXCESSNCT01189786
Ex Vivo T-Cell Depletion of Mobilized Peripheral Blood Stem Cells Via CD34-Selection
A study testing CliniMACS CD34 Reagent system in people with Stem Cell Transplant and Allogeneic, run by Baylor College of Medicine at 2 sites in United States.
Trial summary
Participants are being asked to take part in this study because treatment of his or her disease requires a stem cell transplant. Stem cells or "mother" cells are the source of normal blood cells and lead to recovery of blood counts after bone marrow transplantation. Read more about this study
- Who is it for?
- Ages Up to 70 years
- Conditions the study is for
- Stem Cell Transplant, Allogeneic
- What is being tested?
- CliniMACS CD34 Reagent system
- Type of treatment
- Injection or infusion, Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 241 participants
- Where
- 2 sitesUnited States
- Study dates
- Oct 2010to Nov 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages Up to 70 years
- All sexes
- No healthy volunteers
- Child, Adult, Older adult
Inclusion criteria for Stem Cell Transplant WITH Conditioning (COHORT 1)
- Patient requiring allogeneic SCT
- Age between birth and 70 years
- Patient and/or responsible person able to understand and sign consent
Exclusion criteria for Stem Cell Transplant WITH Conditioning (COHORT 1)
- Active, acute GvHD > grade II or extensive, chronic GvHD
- Severe life, threatening infection
- Pulmonary dysfunction (FEV1, FVC or DLCO 40% of predicted or 3 SD below normal)
- Cardiac dysfunction (LVSF less than 25%)
- Psychiatric disturbance
- Lansky or Karnofsky score < 50%
- The presence of severe hepatic disease (direct bilirubin >3x upper limit of normal and AST > 5x upper limit of normal).
- Creatinine > 3x normal
- Known HIV Positivity
- Pregnancy
Inclusion Criteria for CD34+ Topoff WITHOUT conditioning (COHORT 2)
- Allogeneic SCT Recipient requiring additional cellular therapy
- Age between birth and 70 years
- Patient and/or responsible person able to understand and sign consent
- At least ONE of the following must be answered YES for a patient to be eligible to receive CD34+ topoff:
- Evidence of mixed chimerisms (less than 95% donor cells)
- Evidence of poor bone marrow function (bone marrow cellularity less than 50% with at least one cytopenia)
- Relapsed or persistent disease
Exclusion criteria for CD34+ Topoff WITHOUT conditioning (COHORT 2)
- Active, acute GvHD > grade II or extensive, chronic GvHD
- Severe life, threatening infection
- Known HIV positivity
- Pregnancy
Inclusion Criteria for CD34+ Topoff WITH conditioning (COHORT 3)
- Allogeneic SCT Recipient requiring additional cellular therapy
- Age between birth and 70 years
- Patient and/or responsible person able to understand and sign consent
- At least ONE of the following must be answered YES for a patient to be eligible to receive CD34+ topoff:
- Evidence of mixed chimerisms (less than 95% donor cells)
- Evidence of poor bone marrow function (bone marrow cellularity less than 50% with at least one cytopenia)
- Relapsed or persistent disease
Exclusion criteria for CD34+ Topoff WITH Conditioning (COHORT 3)
- Active, acute GVHD > grade II or extensive, chronic GvHD
- Severe life, threatening infection
- Pulmonary disfunction (FEV1, FVC or DLCO 40% of predicted or 3 SD below normal)
- Cardiac dysfunction (LVSF less than 25%)
- Psychiatric disturbance
- Lansky or Karnofsky score < 50%
- The presence of severe hepatic disease (direct bilirubin > 3x upper limit of normal and AST > 5x upper limit of normal)
- Creatinine > 3x normal
- Known HIV positivity
- Pregnancy
Trial locations and contacts
2 sites in 1 country. Contact the study team or a site near you to ask about taking part.
United States2 sites, 2 recruiting
- Recruiting
Houston Methodist Hospital
Houston, Texas, 77030
Robert Krance, MD, 832-824-4661, rakrance@txch.org
Marlen Dinu, 832-824-4881, mxdinu@txch.org
- Recruiting
Texas Children's Hospital
Houston, Texas, 77030
Robert Krance, MD, 832-824-4661, rakrance@txch.org
Marlen Dinu, 832-824-4881, mxdinu@txch.org
About this study
Official title: Ex Vivo T-Cell Depletion of Mobilized Peripheral Blood Stem Cells Via CD34-Selection (EXCESS)
Participants are being asked to take part in this study because treatment of his or her disease requires a stem cell transplant. Stem cells or "mother" cells are the source of normal blood cells and lead to recovery of blood counts after bone marrow transplantation. Unfortunately, there is not a perfectly matched stem cell donor (like a sister or brother) for the participant and his or her disease does not permit enough time to identify another donor (like someone from a registry list that is not his or her relative) or another suitable donor has not been identified. However, a close relative of the patient has been identified whose stem cells are not a perfect match, but can be used.
Alternatively, the patient may have already received a stem cell transplant but have evidence of mixed chimerism, which means some of the patient's own bone marrow cells are present, rather than all of the donor's cells. This may lead to an increased risk of the disease coming back. Or, the patient may have all donor cells but his or her bone marrow is not working very well, which may lead to frequent blood or platelet (cells that help in clotting blood) transfusions or infection.
Read more
Regardless of the reason, it may be necessary to isolate stem cells from a haploidentical (half-match) donor in order to provide bone marrow function. Because the stem cells from the donor are only half-matched to the participant, the risk of graft-versus-host disease (GvHD) is very high. GvHD is a complication after transplant caused by donor T cells (graft) that attack the transplant recipient, and this complication can cause death after transplant. Thus, it is important that the donor's blood cells are treated to minimize cells that are most likely to attack the host's tissues. This is done by using a special device to capture the CD34+ stem cells from the donor's stem cell product prior to giving the cells to the host. This method minimizes the donor T cells, which are responsible for causing GvHD.
Purpose: In an effort to lower the occurrences and severity of graft-versus-host disease in patients and to lower the rate of transplant failure, investigators would like to specially treat the donor's blood cells to minimize the cells that are most likely to attack the patient's tissues.
Read the detailed description
Participation in this project will last approximately one year with follow-up exams.
Before treatment can begin, stem cells will be collected from the donor (a close relative) that has been selected as the best match for the participant. White blood cells will be collected from the donor. The cells will then be mixed with a special protein, called a CD34 antibody, that binds to the stem cells, which will then be separated out from the white blood cells by a special machine- called a CliniMACS CD34 Reagent System in the laboratory. This is an investigational device that is not approved by the FDA. Although this device is not approved for use in this country, it has been in use for years and is approved in other countries. The stem cells will be collected and given fresh or they can be frozen before they will be given to the participant.
On about days 28, 60, 100, 180 and 365 after the transplant, the participant will have the same tests/evaluations since the time of transplant. For patients who do not develop GvHD, they are not required to have these tests/evaluations.
In addition, for purposes of the study, health-related information will be collected for a year from the time of stem cell infusion. This will be used to determine survival, relapse, infections and GvHD that may occur following transplant.
- Conditions
- Stem Cell Transplant, Allogeneic
- Being tested
- CliniMACS CD34 Reagent system
- Keywords
- Haploidentical Stem Cell Transplant, CD34+ Selection, CliniMACS CD34 Reagent system
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
CliniMACS CD34 Reagent systemDevice
A special machine that separates out the donor cells that have been mixed with a special protein, CD34 antibody, that binds to the stem cells from the white blood cells.
| Study group | Role | What they receive |
|---|---|---|
| Cohort 2: CD34+ cells as a top off Without Conditioning | Experimental | Cohort 2 consists of patients needing additional CD34+ stem cells collected by 'CliniMACS CD34 Reagent system' as a "topoff" without the need for additional conditioning prior to the infusion. These patients who have already received SCT and are receiving CD34+ cells from their original donor for poor graft function, declining chimerism or disease relapse. Receives: Device: CliniMACS CD34 Reagent system |
| Cohort 1: CD34+ Cells for transplant | Experimental | Cohort 1 consists of patients receiving CD34+ selected peripheral blood stem cell transplant with a preceding conditioning regimen (chemotherapy with, or without, radiation). The stem cells will then be separated out from the white blood cells by a special machine- called a CliniMACS CD34 Reagent System in the laboratory. Receives: Device: CliniMACS CD34 Reagent system |
| Cohort 3: CD34+ cells as a top off With Conditioning | Experimental | Cohort 3 consists of patients needing additional CD34+ stem cells collected by 'CliniMACS CD 34+ Reagent System' as a "topoff" with the need for additional conditioning prior to the infusion. These patients who have already received SCT with conditioning and are receiving CD34+ cells from their original donor for poor graft function, declining chimerism or disease relapse. Receives: Device: CliniMACS CD34 Reagent system |
What is being measured
The primary outcome is the main question the study is designed to answer.
For Cohort 1: the rate of primary engraftment 50 days post SCT
Primary engraftment is defined as achievement of absolute neutrophil count (ANC) is greater than or equal to 500/ul for three consecutive days by day 50 post transplant. The treatment regimen will be considered clinically useful if the primary engraftment rate is at least 85%.
Measured: 50 days
For Cohort 2 (Without Conditioning) and Cohort 3 (With Conditioning): The total incidence of overall acute GvHD (greater than or equal to grade 3)
The overall incidence of acute GvHD will be measured 100 days post stem cell transplant. The regimen will be considered acceptable if aGvHD greater than or equal to grade 3 rate is at least 10% or lower.
Measured: 100 days
Secondary outcomes (1)
Assessment of Long Term Survival
Long term survival of recipients of G-CSF mobilized peripheral blood stem cells depleted of T cells by positive selection for the CD34+ antigen
Measured: 1 year
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted27 Aug 2010 (estimated)
- Study startOct 2010
- Primary completionOct 2026 (estimated)
- Study completionNov 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Stem Cell TransplantStudies of the same condition, open and under way.
- More trials run by Baylor College of MedicineThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 241 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Baylor College of Medicine
- Sponsor type
- University, hospital or other
- Collaborators
- Center for Cell and Gene Therapy, Baylor College of Medicine, The Methodist Hospital Research Institute
- Responsible party
- Principal investigator, Robert Krance, Baylor College of Medicine
- Investigators
- Robert Krance, MD, Principal investigator, Baylor College of Medicine
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT01189786
- Sponsor's protocol ID
- H-27251 EXCESS
- Other IDs
- EXCESS
- Acronym
- EXCESS
- Status last verified
- Nov 2025
- First submitted
- 25 Aug 2010
- Last updated
- 3 Dec 2025
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- Yes
Study at a glance
From the registry record, last updated by the sponsor on 3 Dec 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Ex Vivo T-Cell Depletion of Mobilized Peripheral Blood Stem Cells Via CD34-Selection (EXCESS)
- ClinicalTrials.gov ID
- NCT01189786
- Acronym / sponsor ID
- EXCESS / H-27251 EXCESS
- Conditions
- Stem Cell Transplant, Allogeneic
- Keywords
- Haploidentical Stem Cell Transplant, CD34+ Selection, CliniMACS CD34 Reagent system
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 241 participants (estimated)
- Lead sponsor
- Baylor College of MedicineUniversity, hospital or other
- Collaborators
- Center for Cell and Gene Therapy, Baylor College of Medicine, The Methodist Hospital Research Institute
- Study start
- Oct 2010 (actual)
- Primary completion
- Oct 2026 (estimated)
- Study completion
- Nov 2027 (estimated)
- First posted
- 27 Aug 2010 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Participants are being asked to take part in this study because treatment of his or her disease requires a stem cell transplant. Stem cells or "mother" cells are the source of normal blood cells and lead to recovery of blood counts after bone marrow transplantation. Unfortunately, there is not a perfectly matched stem cell donor (like a sister or brother) for the participant and his or her disease does not permit enough time to identify another donor (like someone from a registry list that is not his or her relative) or another suitable donor has not been identified. However, a close relative of the patient has been identified whose stem cells are not a perfect match, but can be used.
Alternatively, the patient may have already received a stem cell transplant but have evidence of mixed chimerism, which means some of the patient's own bone marrow cells are present, rather than all of the donor's cells. This may lead to an increased risk of the disease coming back. Or, the patient may have all donor cells but his or her bone marrow is not working very well, which may lead to frequent blood or platelet (cells that help in clotting blood) transfusions or infection.
Regardless of the reason, it may be necessary to isolate stem cells from a haploidentical (half-match) donor in order to provide bone marrow function. Because the stem cells from the donor are only half-matched to the participant, the risk of graft-versus-host disease (GvHD) is very high. GvHD is a complication after transplant caused by donor T cells (graft) that attack the transplant recipient, and this complication can cause death after transplant. Thus, it is important that the donor's blood cells are treated to minimize cells that are most likely to attack the host's tissues. This is done by using a special device to capture the CD34+ stem cells from the donor's stem cell product prior to giving the cells to the host. This method minimizes the donor T cells, which are responsible for causing GvHD.
Purpose: In an effort to lower the occurrences and severity of graft-versus-host disease in patients and to lower the rate of transplant failure, investigators would like to specially treat the donor's blood cells to minimize the cells that are most likely to attack the patient's tissues.
Detailed description
Participation in this project will last approximately one year with follow-up exams.
Before treatment can begin, stem cells will be collected from the donor (a close relative) that has been selected as the best match for the participant. White blood cells will be collected from the donor. The cells will then be mixed with a special protein, called a CD34 antibody, that binds to the stem cells, which will then be separated out from the white blood cells by a special machine- called a CliniMACS CD34 Reagent System in the laboratory. This is an investigational device that is not approved by the FDA. Although this device is not approved for use in this country, it has been in use for years and is approved in other countries. The stem cells will be collected and given fresh or they can be frozen before they will be given to the participant.
On about days 28, 60, 100, 180 and 365 after the transplant, the participant will have the same tests/evaluations since the time of transplant. For patients who do not develop GvHD, they are not required to have these tests/evaluations.
In addition, for purposes of the study, health-related information will be collected for a year from the time of stem cell infusion. This will be used to determine survival, relapse, infections and GvHD that may occur following transplant.
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Cohort 2: CD34+ cells as a top off Without Conditioning | Experimental | Device: CliniMACS CD34 Reagent systemCohort 2 consists of patients needing additional CD34+ stem cells collected by 'CliniMACS CD34 Reagent system' as a "topoff" without the need for additional conditioning prior to the infusion. These patients who have already received SCT and are receiving CD34+ cells from their original donor for poor graft function, declining chimerism or disease relapse. |
| Cohort 1: CD34+ Cells for transplant | Experimental | Device: CliniMACS CD34 Reagent systemCohort 1 consists of patients receiving CD34+ selected peripheral blood stem cell transplant with a preceding conditioning regimen (chemotherapy with, or without, radiation). The stem cells will then be separated out from the white blood cells by a special machine- called a CliniMACS CD34 Reagent System in the laboratory. |
| Cohort 3: CD34+ cells as a top off With Conditioning | Experimental | Device: CliniMACS CD34 Reagent systemCohort 3 consists of patients needing additional CD34+ stem cells collected by 'CliniMACS CD 34+ Reagent System' as a "topoff" with the need for additional conditioning prior to the infusion. These patients who have already received SCT with conditioning and are receiving CD34+ cells from their original donor for poor graft function, declining chimerism or disease relapse. |
Who may qualify
- Ages
- Up to 70 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult, Older adult
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| CliniMACS CD34 Reagent systemA special machine that separates out the donor cells that have been mixed with a special protein, CD34 antibody, that binds to the stem cells from the white blood cells. | Device | Cohort 1: CD34+ Cells for transplant, Cohort 2: CD34+ cells as a top off Without Conditioning, Cohort 3: CD34+ cells as a top off With Conditioning |
Primary outcome
For Cohort 1: the rate of primary engraftment 50 days post SCT
Time frame: 50 days
Primary engraftment is defined as achievement of absolute neutrophil count (ANC) is greater than or equal to 500/ul for three consecutive days by day 50 post transplant. The treatment regimen will be considered clinically useful if the primary engraftment rate is at least 85%.
For Cohort 2 (Without Conditioning) and Cohort 3 (With Conditioning): The total incidence of overall acute GvHD (greater than or equal to grade 3)
Time frame: 100 days
The overall incidence of acute GvHD will be measured 100 days post stem cell transplant. The regimen will be considered acceptable if aGvHD greater than or equal to grade 3 rate is at least 10% or lower.
1 secondary outcome
Assessment of Long Term Survival
Time frame: 1 year
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 3 Dec 2025.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Robert Krance, MD principal investigator
Baylor College of Medicine
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing CliniMACS CD34 Reagent system in people with Stem Cell Transplant and Allogeneic, run by Baylor College of Medicine at 2 sites in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 3 Dec 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Robert Krance, MD (832-824-4661, rakrance@txch.org), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
For Cohort 1: the rate of primary engraftment 50 days post SCT (time frame: 50 days). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 3 Dec 2025.