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Conditioning Regimen for Allogeneic Hematopoietic Stem-Cell Transplantation

PEDS024, Phase I/II Feasibility Study of Busulfan Fludarabine and Thiotepa Conditioning Regimen for Allogeneic Hematopoietic Stem-Cell Transplantation (HSCT) for Children With Non-Malignant Disorders

Status
Completed
Phases
Phase 1Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03513328
Enrollment
6
Registered
2018-05-01
Start date
2018-06-15
Completion date
2023-02-19
Last updated
2023-09-15

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Acquired Anemia Hemolytic, Acquired Neutropenia in Newborn, Acquired Thrombocytopenia, Adrenoleukodystrophy, Bone Marrow Failure Syndrome, Chronic Granulomatous Disease, Common Variable Immunodeficiency, Diamond Blackfan Anemia, Hemophagocytic Lymphohistiocytoses, Hurler Syndrome, Mannosidosis, Severe Combined Immunodeficiency, Sickle Cell Disease, Thalassemia, Wiskott-Aldrich Syndrome, X-linked Lymphoproliferative Disease

Keywords

human leukocyte antigen (HLA)

Brief summary

In this study, the investigators test 2 dose levels of thiotepa (5 mg/kg and 10 mg/kg) added to the backbone of targeted reduced dose IV busulfan, fludarabine and rabbit anti-thymocyte globulin (rATG) to determine the minimum effective dose required for reliable engraftment for subjects undergoing hematopoietic stem cell transplantation for non-malignant disease.

Detailed description

Hematopoietic stem cell transplantation is the only curative choice for a number of inherited bone marrow failure syndromes, hemoglobinopathies, metabolic disorders and primary immune deficiencies. While survival of these patients is typically better than survival of patients with malignancies, toxicities of conditioning regimens and failure of engraftment remain challenges. Most children with non-malignant disorders present with normocellular or even hypercellular bone marrow, posing a barrier to engraftment and requiring intensive conditioning. Commonly used backbone of busulfan and fludarabine, although well tolerated, results in variable engraftment, in particular with mismatched unrelated donors and cord blood recipients. In this study, the investigators test 2 dose levels of thiotepa (5 mg/kg and 10 mg/kg) added to the backbone of targeted reduced dose IV busulfan, fludarabine and rabbit anti-thymocyte globulin (rATG) in order to determine the minimum effective dose required for reliable engraftment. Subjects are stratified in groups A and B based the risk of graft failure.

Interventions

DRUGThiotepa--single daily dose

Conditioning regimen for hematopoietic stem-cell transplant. Single daily IV dose of Thiotepa at 5 mg/kg.

DRUGThiotepa--escalated dose

Twice daily IV dose of Thiotepa at 5 mg/kg, twelve hours apart, 10mg/kg total.

Sponsors

Live Like Bella Pediatric Cancer Research
CollaboratorOTHER
University of Florida
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
SEQUENTIAL
Primary purpose
TREATMENT
Masking
NONE

Intervention model description

The study builds in rules for escalation of thiotepa dose based on graft failure by day 42. Patients are stratified in two groups A (lower risk of graft failure) and B (higher risk of graft failure). Patients undergoing 10/10 HLA matched bone marrow and peripheral blood transplants are assigned to Group A, and patients receiving \<10/10 matched bone marrow or peripheral blood, or receiving cord blood, even if fully matched, are assigned to Group B. If criteria for thiotepa dose escalation are met first in Group A, which has a lower risk of graft failure, thiotepa dose will be escalated for all subjects (Groups A and B). If criteria for thiotepa dose escalation are met first in Group B, dose will be escalated only in Group B and Group A will continue enrolling patients at a lower dose level.

Eligibility

Sex/Gender
ALL
Age
3 Months to 39 Years
Healthy volunteers
No

Inclusion criteria

* Diagnoses: * Hemoglobinopathies (e.g. thalassemia or sickle cell disease), * Cytopenias (e.g.Diamond-Blackfan anemia, congenital or acquired neutropenia, congenital or acquired thrombocytopenia, congenital or acquired anemia, and others, regardless clonality), * Hemophagocytic lymphohistiocytosis, * Primary immunodeficiencies (e.g. Wiscott Aldrich Syndrome, chronic granulomatous disease, common variable immune deficiency, X-linked lymphoproliferative disease, NK+ severe combined immune deficiencies), * Metabolic disorders (Hurler's syndrome, mannosidosis, adrenal leuko-dystrophy) * Other non-malignant disorders for which there is published evidence that HSCT (hematopoietic stem cell transplant) is a curative therapy. * Donor Requirements * Related or unrelated donor who is suitable and willing to donate bone marrow or peripheral blood stem cells. HLA typing should be done by high-resolution typing at A, B, C, DrB1 and DQ loci and the donor should be at a minimum ≥8/10 match (with one antigen/allele mismatch allowed at A, B, or C-loci and other at DQ loci). * Cord blood units must be matched at a minimum of 6/8 antigens/alleles at A, B, C and DrB1 loci. High resolution typing at all loci is required. The minimum TNC dose pre-cryopreservation must be ≥3.7 x10\^7/kg of recipient's weight, if a single cord blood unit is used, or at least 2x10\^7/kg per unit, if two cord blood units are used. The mismatches cannot be at the same loci (e.g. double A mismatch). * Haploidentical related stem cell donor who is suitable and willing to donate peripheral blood stem cells. T-cell depletion is required if haploidentical donors are used. Pharmacologic GVHD prophylaxis will not be used for T-cell depleted transplant recipients. * Adequate organ function defined as: * Cardiac: ejection fraction ≥55% or shortening fraction ≥30% * creatinine clearance ≥70 ml/min/1.73m2 * Pulse oximetry \>95% on room air or FEV1/DLCO \>60% * LFTs \< 3 x ULN, Total bilirubin \<3 mg/dl (unless due to non-hepatic cause (e.g. Gilbert's syndrome or hemolysis) * Lansky/Karnofsky score ≥60% * Written informed consent obtained from the subject or parental/guardian permission ± child's assent per institutional guidelines * Women of childbearing potential (WOCBP) must be using an adequate method of contraception to avoid pregnancy for at least 1 month after completion of conditioning. WOCBP include any woman who has experienced menarche and who has not undergone successful surgical sterilization (hysterectomy, bilateral tubal ligation, or bilateral oophorectomy) or who is not post-menopausal. Post-menopause is defined as: * Amenorrhea that has lasted for ≥ 12 consecutive months without another cause, or * For women with irregular menstrual periods who are taking hormone replacement therapy (HRT), a documented serum follicle-stimulating hormone (FSH) level of greater than 35 mIU/mL. * Males with female partners of childbearing potential must agree to use physician-approved contraceptive methods (e.g., abstinence, condoms, or vasectomy) for at least one month after completion of conditioning.

Exclusion criteria

* Diagnoses that do not require myeloablative transplant for cure (e.g. NK- SCID patients), unless the subject previously did not engraft with non-myeloablative or reduced intensity conditioning transplant. * Known or suspected sensitivity to chemotherapy or radiation (e.g Fanconi's anemia, Dyskeratosis congenita, Ligase IV deficiency, etc). * Subjects with fast-progressing neurodegenerative disorders (e.g. Krabbe disease or adrenal leukodystrophy with Loes score of ≥10) * Cytopenias with increased blasts (\>5%) * Presence of anti-donor HLA antibodies (positive anti-donor HLA antibody is defined as a positive cross-match test of any titer (by complement-dependent cytotoxicity or flow cytometric testing) or the presence of anti-donor HLA antibody to the high expression loci HLA-A, B, C, DRB1 with mean fluorescence intensity (MFI)\>3000 by solid phase * Prior allogeneic stem cell transplant, except for patients with immune deficiencies who underwent previous non-myeloablative or reduced intensity transplants. * Haploidentical donor using in vivo T-cell depletion (e.g. post-transplant cyclophosphamide). * Uncontrolled bacterial, viral, or fungal infection at the time of enrollment. Uncontrolled is defined as currently taking medication and with progression or no clinical improvement on adequate medical treatment. * Seropositive for HIV * Active Hepatitis B or C determined by a detectable viral load of HBV or HCV by PCR * Bridging fibrosis or liver cirrhosis * Females or males of childbearing potential who are unwilling or unable to use an acceptable method to avoid pregnancy for the entire study period and for at least 1 months after the end of conditioning * Females who are pregnant or breastfeeding * History of any other disease, metabolic dysfunction, physical examination finding, or clinical laboratory finding giving reasonable suspicion of a disease or condition that contraindicates the use of protocol therapy or that might affect the interpretation of the results of the study or that puts the subject at high risk for treatment complications, in the opinion of the treating physician. * Subjects demonstrating an inability to understand the study and comply with the study and/or follow-up procedures

Design outcomes

Primary

MeasureTime frameDescription
Assessment of Minimum Effective Dose (MED) of ThiotepaDay 42Assess the MED of thiotepa in combination with reduced-dose busulfan, fludarabine and rATG required to achieve engraftment in \>90% subjects undergoing hematopoietic stem cell transplantation for non-malignant disorders.

Secondary

MeasureTime frameDescription
Percentage of Subjects Without Disease Recurrence Who Are Alive at 24 Months Post TransplantMonth 24Percentage of subjects who initiated conditioning regimen and are without evidence of underlying disease (DFS).
Percentage of Subjects Alive at 24 Months Post Transplant (OS)Month 24Percentage of subjects who initiated conditioning regimen and are alive at 24 months post transplant (OS).
Evaluation of Transplant-related MortalityMonth 12Percentage of subjects who initiated conditioning regimen and who died due to a cause unrelated to the underlying disease.
Percentage of Subjects With Graft Rejection/Failure.Day 42; Day 365Percentage of all subjects who initiated conditioning regimen and have sustained engraftment failure.
Percentage of Participants With Chronic Graft-versus-host Disease (cGVHD)Month 24Measures the frequency of chronic graft-vs-host disease in Group A participants
Percentage of Participants With Transplant-related Complications24 monthsComplications gathered via CIBMTR (Center for International Blood & Marrow Transplant Research) post-transplant form was tabulated and described by treatment received.
Number of Participants With Grade 2-4 Acute Graft-versus-host Disease (GVDH)Month 12Graft-versus host disease symptoms measured using Modified Glucksberg Staging Criteria. (Scale 0-4; with 4 being most severe)

Countries

United States

Participant flow

Recruitment details

Subjects were enrolled from June 2018 through January 2021. Only Arm A enrolled patients due to change in clinical practice. No donors with HLA mismatch enrolled in this study.

Participants by arm

ArmCount
Group A--Thiotepa Single Dose
Fully matched 10/10 subjects with lower risk of graft failure. Subjects will undergo 10/10 HLA (human leukocyte antigen) matched bone marrow and peripheral blood transplant. Subjects receive combination of single daily dose thiotepa (5 mg/kg) added to the backbone of targeted reduced dose IV busulfan, fludarabine and rabbit anti-thymocyte globulin (rATG). Thiotepa--single daily dose: Conditioning regimen for hematopoietic stem-cell transplant. Single daily IV dose of Thiotepa at 5 mg/kg.
6
Group A--Thiotepa Escalated Dose
Fully matched 10/10 subjects with lower risk of graft failure. Subjects will undergo 10/10 HLA (human leukocyte antigen) matched bone marrow and peripheral blood transplant. Subjects receive combination of escalated dose of thiotepa (10 mg/kg) added to the backbone of targeted reduced dose IV busulfan, fludarabine and rabbit anti-thymocyte globulin (rATG). Thiotepa--escalated dose: Twice daily IV dose of Thiotepa at 5 mg/kg, twelve hours apart, 10mg/kg total.
0
Group B--Thiotepa Single Dose
Subjects with higher risk of graft failure. Subjects will undergo transplant with \<10/10 bone marrow or peripheral blood match, or receiving cord blood transplant. Subjects receive combination of single daily dose thiotepa (5 mg/kg) added to the backbone of targeted reduced dose IV busulfan, fludarabine and rabbit anti-thymocyte globulin (rATG). Thiotepa--single daily dose: Conditioning regimen for hematopoietic stem-cell transplant. Single daily IV dose of Thiotepa at 5 mg/kg.
0
Group B--Thiotepa Escalated Dose
Subjects with higher risk of graft failure. Subjects will undergo transplant with \<10/10 bone marrow or peripheral blood match, or receiving cord blood transplant. Subjects receive combination of escalated dose of thiotepa (10 mg/kg)added to the backbone of targeted reduced dose IV busulfan, fludarabine and rabbit anti-thymocyte globulin (rATG). Thiotepa--escalated dose: Twice daily IV dose of Thiotepa at 5 mg/kg, twelve hours apart, 10mg/kg total.
0
Total6

Baseline characteristics

CharacteristicGroup A--Thiotepa Single DoseTotalGroup B--Thiotepa Escalated DoseGroup B--Thiotepa Single DoseGroup A--Thiotepa Escalated Dose
Age, Categorical
<=18 years
4 Participants4 Participants
Age, Categorical
>=65 years
0 Participants0 Participants
Age, Categorical
Between 18 and 65 years
2 Participants2 Participants
Age, Continuous13 years13 years
Ethnicity (NIH/OMB)
Hispanic or Latino
0 Participants0 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
6 Participants6 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants
Race (NIH/OMB)
Asian
0 Participants0 Participants
Race (NIH/OMB)
Black or African American
2 Participants2 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants
Race (NIH/OMB)
White
4 Participants4 Participants
Region of Enrollment
United States
6 participants6 participants
Sex: Female, Male
Female
2 Participants2 Participants0 Participants0 Participants0 Participants
Sex: Female, Male
Male
4 Participants4 Participants0 Participants0 Participants0 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
deaths
Total, all-cause mortality
0 / 60 / 00 / 00 / 0
other
Total, other adverse events
6 / 60 / 00 / 00 / 0
serious
Total, serious adverse events
0 / 60 / 00 / 00 / 0

Outcome results

Primary

Assessment of Minimum Effective Dose (MED) of Thiotepa

Assess the MED of thiotepa in combination with reduced-dose busulfan, fludarabine and rATG required to achieve engraftment in \>90% subjects undergoing hematopoietic stem cell transplantation for non-malignant disorders.

Time frame: Day 42

Population: MED dose of thiotepa in group A was determined to be 5 mg/kg in combination with Fludarabine and rATG. All six patients engrafted by day 42 using this dose. No subsequent escalation was done.

ArmMeasureValue (NUMBER)
Group A--Thiotepa Single DoseAssessment of Minimum Effective Dose (MED) of Thiotepa5 mg/kg
Secondary

Evaluation of Transplant-related Mortality

Percentage of subjects who initiated conditioning regimen and who died due to a cause unrelated to the underlying disease.

Time frame: Month 12

Population: Transplant related mortality at 12 months post transplant was 0% (95% CI 0-46%) in Group A. Transplant-related mortality could not have been evaluated for group B due to lack of enrollment

ArmMeasureValue (NUMBER)
Group A--Thiotepa Single DoseEvaluation of Transplant-related Mortality0 Percentage of patients
Secondary

Number of Participants With Grade 2-4 Acute Graft-versus-host Disease (GVDH)

Graft-versus host disease symptoms measured using Modified Glucksberg Staging Criteria. (Scale 0-4; with 4 being most severe)

Time frame: Month 12

Population: 1 of 6 patients developed GVHD grade 2-4.

ArmMeasureValue (NUMBER)
Group A--Thiotepa Single DoseNumber of Participants With Grade 2-4 Acute Graft-versus-host Disease (GVDH)1 Number of patients
Secondary

Percentage of Participants With Chronic Graft-versus-host Disease (cGVHD)

Measures the frequency of chronic graft-vs-host disease in Group A participants

Time frame: Month 24

Population: cGVHD in 2 of 6 participants

ArmMeasureValue (NUMBER)
Group A--Thiotepa Single DosePercentage of Participants With Chronic Graft-versus-host Disease (cGVHD)33 Percentage of patients
Secondary

Percentage of Participants With Transplant-related Complications

Complications gathered via CIBMTR (Center for International Blood & Marrow Transplant Research) post-transplant form was tabulated and described by treatment received.

Time frame: 24 months

Population: Percentages of patient at risk for complications during first 2 years post transplant

ArmMeasureGroupValue (NUMBER)
Group A--Thiotepa Single DosePercentage of Participants With Transplant-related ComplicationsMucositis - 1st year post transplant100 Percentage of patients
Group A--Thiotepa Single DosePercentage of Participants With Transplant-related ComplicationsViral reactivations - first year post transplant67 Percentage of patients
Group A--Thiotepa Single DosePercentage of Participants With Transplant-related ComplicationsCovid 19 Infection first year post transplant17 Percentage of patients
Group A--Thiotepa Single DosePercentage of Participants With Transplant-related ComplicationsBacterial Infection first year post transplant33 Percentage of patients
Group A--Thiotepa Single DosePercentage of Participants With Transplant-related ComplicationsHemorrhagic Cystitis in first year post transplant17 Percentage of patients
Group A--Thiotepa Single DosePercentage of Participants With Transplant-related ComplicationsViral reactivations in 2nd year post transplant67 Percentage of patients
Group A--Thiotepa Single DosePercentage of Participants With Transplant-related ComplicationsCovid 19 infection in the 2nd year post transplant17 Percentage of patients
Group A--Thiotepa Single DosePercentage of Participants With Transplant-related ComplicationsBacterial Infections in the 2nd year post transplant17 Percentage of patients
Secondary

Percentage of Subjects Alive at 24 Months Post Transplant (OS)

Percentage of subjects who initiated conditioning regimen and are alive at 24 months post transplant (OS).

Time frame: Month 24

Population: At 24 month OS and DFS was 100% (95% CI 54-100%) in group A, the OS and DFS could not have been evaluated for group B due to lack of enrollment

ArmMeasureValue (NUMBER)
Group A--Thiotepa Single DosePercentage of Subjects Alive at 24 Months Post Transplant (OS)100 Percentage of patients
Secondary

Percentage of Subjects With Graft Rejection/Failure.

Percentage of all subjects who initiated conditioning regimen and have sustained engraftment failure.

Time frame: Day 42; Day 365

Population: Risk of rejection was determined in Group A. None of the patients rejected the graft = 0% (95% CI 0-46%) either at Day 42 or Day 365

ArmMeasureValue (NUMBER)
Group A--Thiotepa Single DosePercentage of Subjects With Graft Rejection/Failure.0 Percentage of participants
Secondary

Percentage of Subjects Without Disease Recurrence Who Are Alive at 24 Months Post Transplant

Percentage of subjects who initiated conditioning regimen and are without evidence of underlying disease (DFS).

Time frame: Month 24

Population: At 24 month OS and DFS was 100% (95% CI 54-100%) in group A, the OS and DFS could not have been evaluated for group B due to lack of enrollment

ArmMeasureValue (NUMBER)
Group A--Thiotepa Single DosePercentage of Subjects Without Disease Recurrence Who Are Alive at 24 Months Post Transplant100 Percentage of patients

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026