Skip to main content
OpenTrials
Active, Not Recruiting

NCT Number: NCT04904588

HLA-Mismatched Unrelated Donor Hematopoietic Cell Transplantation With Post-Transplantation Cyclophosphamide

This is a prospective, multi-center, Phase II study of hematopoietic cell transplantation (HCT) using human leukocyte antigen (HLA)-mismatched unrelated donors (MMUD) for peripheral blood stem cell transplant in adults and bone marrow stem cell transplant in children. Post-transplant cyclophosphamide (PTCy), tacrolimus and mycophenolate mofetil (MMF) will be used for for graft versus host disease (GVHD) prophylaxis. This trial will study how well this treatment works in patients with hematologic malignancies.

Active, Not Recruiting

This study is active but is not currently recruiting participants.

Key information

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Stratum 1 Recipient Inclusion Criteria:

  • Age > 18 years and < 66 years (chemotherapy-based conditioning) or < 61 years (total body irradiation [TBI]-based conditioning) at the time of signing informed consent
  • Planned MAC regimen as defined per protocol
  • Available partially HLA-MMUD (4/8-7/8 at HLA-A, -B, -C, and -DRB1 is required) with age < 35 years
  • Product planned for infusion is PBSC
  • HCT Comorbidity Index (HCT-CI) < 5
  • One of the following diagnoses:
  • Acute myeloid leukemia (AML) acute lymphoblastic leukemia (ALL), or other acute leukemia in 1st remission or beyond with ≤ 5% marrow blasts and no circulating blasts or evidence of extra-medullary disease. Documentation of bone marrow assessment will be accepted within 45 days prior to the anticipated start of conditioning.
  • Patients with myelodysplastic syndrome (MDS) with no circulating blasts and with < 10% blasts in the bone marrow (higher blast percentage allowed in MDS due to lack of differences in outcomes with < 5% or 5-10% blasts in MDS). Documentation of bone marrow assessment will be accepted within 45 days prior to the anticipated start of conditioning.
  • Cardiac function: Left ventricular ejection fraction > 45% based on most recent echocardiogram or multigated acquisition scan (MUGA) results
  • Estimated creatinine clearance > 60 mL/min calculated by equation
  • Pulmonary function: diffusing capacity of the lungs for carbon monoxide (DLCO) corrected for hemoglobin > 50% and forced expiratory volume in first second (FEV1) predicted > 50% based on most recent pulmonary function test results
  • Liver function acceptable per local institutional guidelines
  • Karnofsky performance status (KPS) of > 70%
  • Subjects ≥ 18 years of age or legally authorized representative must have the ability to give informed consent according to applicable regulatory and local institutional requirements.

Stratum 2 Recipient Inclusion Criteria

  • Age > 18 years at the time of signing informed consent
  • Planned NMA/RIC regimen as defined per protocol
  • Available partially HLA-MMUD (4/8-7/8 at HLA-A, -B, -C, and -DRB1 is required) with age < 35 years
  • Product planned for infusion is PBSC
  • One of the following diagnoses:
  • Patients with acute leukemia or chronic myeloid leukemia (CML) with no circulating blasts, no evidence of extramedullary disease, and with < 5% blasts in the bone marrow. Documentation of bone marrow assessment will be accepted within 45 days prior to the anticipated start of conditioning.
  • Patients with MDS with no circulating blasts and with < 10% blasts in the bone marrow (higher blast percentage allowed in MDS due to lack of differences in outcomes with < 5% or 5-10% blasts in MDS.) Documentation of bone marrow assessment will be accepted within 45 days prior to the anticipated start of conditioning.
  • Patients with chronic lymphocytic leukemia (CLL) or other leukemias (including prolymphocytic leukemia) with chemosensitive disease at time of transplantation
  • Patients with lymphoma with chemosensitive disease at the time of transplantation
  • Cardiac function: Left ventricular ejection fraction > 45% based on most recent echocardiogram or MUGA results with no clinical evidence of heart failure
  • Estimated creatinine clearance > 60 mL/min calculated by equation
  • Pulmonary function: DLCO corrected for hemoglobin > 50% and FEV1 predicted > 50% based on most recent pulmonary function test results
  • Liver function acceptable per local institutional guidelines
  • KPS of > 60%
  • Subjects ≥ 18 years of age or legally authorized representative must have the ability to give informed consent according to applicable regulatory and local institutional requirements.

Stratum 3 Recipient Inclusion Criteria

  • Age > 1 years and < 21 years at the time of signing informed consent
  • Partially HLA-MMUD (4/8-7/8 at HLA-A, -B, -C, and -DRB1 is required) with age < 35 years
  • Product planned for infusion is BM
  • Planned MAC regimen as defined per protocol
  • One of the following diagnosis:
  • AML in 1st remission or beyond with ≤ 5% marrow blasts, no circulating blasts or evidence of extra-medullary disease. Pre-transplant MRD testing will be performed as per standard of practice at the treating institution. Patients with any MRD status are eligible and should be enrolled at the discretion of provider. Documentation of bone marrow assessment will be accepted within 45 days prior to the anticipated start of conditioning.
  • Patients MDS with no circulating blasts and less than 10% blasts in the bone marrow. Documentation of bone marrow assessment will be accepted within 45 days prior to the anticipated start of conditioning.
  • ALL in 1st remission or beyond with ≤ 5% marrow blasts, no circulating blasts, or evidence of extra-medullary disease. Pre-transplant MRD testing will be performed as standard practice at the treating institution with the goal of achieving MRD of <0.01%. Patients with any MRD status are eligible and should be enrolled at the discretion of provider. Documentation of bone marrow assessment will be accepted within 45 days prior to the anticipated start of conditioning.
  • Other leukemia (mixed-phenotype acute leukemia [MPAL], CML, or other leukemia) in morphologic remission with ≤ 5% marrow blasts and no circulating blasts or evidence of extramedullary disease. Documentation of bone marrow assessment will be accepted within 45 days prior to the anticipated start of conditioning.
  • Chemotherapy sensitive lymphoma in at least partial remission (PR)
  • KPS or Lansky performance score ≥ 70%
  • Cardiac function: Left ventricular ejection fraction of ≥ 50% and shortening fraction of ≥ 27% based on most recent echocardiogram
  • Glomerular Filtration Rate (GFR) of ≥ 60ml/min/1.73m2 measured by nuclear medicine scan or calculated from a 24 hour urine collection
  • Pulmonary function: DLCO corrected for hemoglobin, FEV1, and Forced Vital Capacity (FVC) of ≥50% if able to perform pulmonary function tests. If unable to perform pulmonary function tests, must have a resting pulse oximetry of >92% without supplemental oxygen.
  • Hepatic: Total bilirubin ≤ 2.5 mg/dL and alanine aminotransferase (ALT), aspartate aminotransferase (AST) < 3x the upper limit of normal
  • Legal guardian permission must be obtained for subjects < 18 years of age. Pediatric subjects will be included in age appropriate discussion in order to obtain assent.
  • Subjects ≥ 18 years of age or legally authorized representative must have the ability to give informed consent according to applicable regulatory and local institutional requirements.

Donor Inclusion Criteria:

  • Must be unrelated to the subject and high-resolution HLA-matched at 4/8, 5/8, 6/8, or 7/8 (HLA-A, -B, -C, and -DRB1)
  • Donor must be typed at high-resolution for a minimum of HLA-A, -B, -C, -DRB1, -DQB1, and -DPB1
  • Age > 18 years and < 35 years at the time of signing informed consent
  • Meet the donor registries' medical suitability requirements for PBSC or BM donation
  • Must undergo eligibility screening according to current Food and Drug Administration (FDA) requirements. Donors who do not meet one or more of the donor screening requirements may donate under urgent medical need.
  • Must agree to donate PBSC (or BM for stratum 3)
  • Must have the ability to give standard (non-study) informed consent according to applicable donor regulatory requirements

Recipient Exclusion Criteria (Strata 1, 2 and 3):

  • Suitable HLA-matched related or 8/8 high-resolution matched unrelated donor available
  • Subject unwilling or unable to give informed consent, or unable to comply with the protocol including required follow-up and testing
  • Primary myelofibrosis or myelofibrosis secondary to essential thrombocythemia, polycythemia vera, or MDS with grade 4 marrow fibrosis
  • Subjects with a prior allogeneic HSC transplant
  • Subjects with an autologous HSC transplant within the past 3 months
  • Females who are breast-feeding or pregnant
  • Uncontrolled bacterial, viral or fungal infection at the time of the transplant preparative regimen
  • Concurrent enrollment on other interventional GVHD clinical trial (enrollment on supportive care trials may be allowed after discussion with Principal Investigators)
  • Subjects who undergo desensitization to reduce anti-donor HLA antibody levels prior to transplant.
  • Patients who are HIV+ with persistently positive viral load. HIV-infected patients on effective anti-retroviral therapy with undetectable viral load within 6 months are eligible for this trial.

Donor Exclusion Criteria:

  • Donor unwilling or unable to donate
  • Recipient positive anti-donor HLA antibodies against a mismatched HLA in the selected donor determined by the presence of donor specific HLA antibodies (DSA) to any mismatched HLA allele/antigen at any of the following loci (HLA-A, -B, -C, -DRB1, DRB3, DRB4, DRB5, -DQA1, -DQB1, -DPA1, -DPB1) with median fluorescence intensity (MFI) >3000 by microarray-based single antigen bead testing. In patients receiving red blood cell or platelet transfusions, DSA evaluation must be performed or repeated post-transfusion and prior to donor mobilization and initiation of recipient preparative regimen.

Treatment and study plan

busulfan

Drug

Given IV or PO pre-transplant as part of conditioning regimen

Other names: Busulfex®

Fludarabine

Drug

Given IV pre-transplant as part of conditioning regimen

Other names: Fludara®

total-body irradiation

Radiation

Administered pre-transplant as part of conditioning regimen

Other names: TBI

Cyclophosphamide

Drug

Given IV pre-transplant as part of conditioning regimen

Other names: Cytoxan®

melphalan

Drug

Given IV pre-transplant as part of conditioning regimen

PBSC Hematopoietic Stem Cell Transplantation (HSCT)

Procedure

Peripheral blood stem cell graft is infused from a mismatched unrelated donor on Day 0.

Other names: PBSC HSCT, PBSC HCT, PBSC Transplantation

Bone Marrow Hematopoietic Stem Cell Transplantation

Procedure

Bone marrow graft is infused from a mismatched unrelated donor on Day 0.

Other names: BM HSCT, BM HCT, Bone Marrow Transplantation

Post-transplant Cyclophosphamide

Drug

Cyclophosphamide (50 mg/kg) is administered on Day +3 and on Day +4 post-transplant as an IV infusion over 1-2 hours.

Other names: Cytoxan®

Mesna

Drug

Mesna is given in divided doses IV 30 min pre- and at 3, 6, and 8 hours post-cyclophosphamide.

Other names: Mesnex®

Tacrolimus

Drug

Tacrolimus is given at a dose of 0.05 mg/kg PO or an IV dose of 0.03 mg/kg of ideal body weight (IBW) starting on Day +5 post-transplant with taper recommended at 90-100 days post HCT.

Mycophenolate mofetil

Drug

Mycophenolate mofetil (MMF) is given at a dose of 15 mg/kg three times daily IV or PO from Day +5 to Day +35 post-transplant.

Other names: MMF, Cellcept®

Patient-Reported Outcomes

Other

Survey assessments will be administered to study participants pre- and post-transplant.

Primary outcomes

  1. Overall Survival

    Time frame: 1 year post HCT

Secondary outcomes

  1. Event-free survival

    Time frame: 1 year post-HCT

    Defined as graft failure, relapse or progression of underlying disease, death, grade 3-4 acute GVHD, or NIH-severe chronic GVHD.

  2. GVHD, relapse free survival

    Time frame: 1 year post-HCT

    Defined as relapse or progression of underling disease, graft failure, grade III-IV acute GVHD, chronic GVHD requiring systemic immune suppression, or death by any cause.

  3. Modified GVHD, relapse free survival

    Time frame: 1 year post-HCT

    Defined as relapse or progression of underling disease, graft failure, grade III-IV acute GVHD, NIH moderate or severe chronic GVHD, or death by any cause.

  4. Progression-free survival

    Time frame: 1 year post-HCT

  5. Cumulative incidence of nonrelapse mortality

    Time frame: Day +100 and 1 year post-HCT

  6. Event-Free Survival based on donor HLA match grade and donor age (7/8 versus <7/8)

    Time frame: 1 year post-HCT

  7. Overall Survival based on donor HLA match grade and donor age (7/8 versus <7/8)

    Time frame: 1 year post-HCT

  8. Cumulative incidence of neutrophil recovery

    Time frame: Day +100 post-HCT

    Defined as neutrophil count ≥500/mm^3 for 3 consecutive days post-HCT.

  9. Kinetics of neutrophil recovery

    Time frame: Day +100 post-HCT

    Defined as the evaluation of the time it takes for neutrophil count recovery to occur in the study subjects.

  10. Cumulative incidence of platelet recovery

    Time frame: Day +100 post-HCT

    Defined as platelet count ≥20,000/mm^3 or ≥50,000/mm^3 with no platelet transfusions within seven days.

  11. Kinetics of platelet recovery

    Time frame: Day +100 post-HCT

    Defined as the evaluation of the time it takes for platelet count recovery to occur in the study subjects.

  12. Cumulative incidence of primary graft failure

    Time frame: Day +28 post-HCT

  13. Donor chimerism

    Time frame: Day +100 post-HCT

    Strata 2 and 3 only. Percent of donor chimerism via peripheral blood

  14. Cumulative incidence of acute GVHD

    Time frame: Day +100 post-HCT

  15. Cumulative incidence of chronic GVHD

    Time frame: 1 year post-HCT

  16. Cumulative incidence of BK and cytomegalovirus (CMV) viral infections

    Time frame: Days +100 and +180 post-HCT

  17. Cumulative incidence of relapse/progression

    Time frame: 1 year post-HCT

  18. Incidence of cytokine release syndrome (CRS)

    Time frame: Day +14 post-HCT

    Overall incidence of CRS of any grade and grade 3 or 4 CRS post-transplant

  19. Cumulative incidence of secondary graft failure

    Time frame: 1 year post-HCT

  20. Overall Toxicity

    Time frame: 1 year post-HCT

    To tabulate adverse events (AEs) experienced by recipients, defined as grade 3-5 unexpected and Grade 5 expected AEs, according to CTCAE version 5.0.

Sponsors and collaborators

Lead sponsor

Center for International Blood and Marrow Transplant Research

Network

Collaborators

  • National Marrow Donor Program

Registry information

Official study title

A Multi-Center, Phase II Trial of HLA-Mismatched Unrelated Donor Hematopoietic Cell Transplantation With Post-Transplantation Cyclophosphamide for Patients With Hematologic Malignancies

Acronym: ACCESS

Important dates

Study start
2021
Primary completion
2026
Study completion
2026
First posted
May 27, 2021
Registry last updated
Mar 18, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Published trials that share one or more normalized conditions with this study.