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CSF-1R Inhibitor, Axatilimab, for Prevention of Acute and Chronic GVHD After HLA-Matched Related and Unrelated Donor Allogeneic Stem Cell Transplantation

Phase II Open-Label, Randomized-Controlled Trial of CSF-1R Inhibitor, Axatilimab, for Prevention of Acute and Chronic GVHD After HLA-Matched Related and Unrelated Donor Allogeneic Stem Cell Transplantation

Status
Not yet recruiting
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07808112
Acronym
ABRAXAS
Enrollment
72
Registered
2026-09-08
Start date
2026-11-01
Completion date
2031-11-01
Last updated
2026-09-08

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

Conditions

Graft -Versus-host-disease

Keywords

hematologic malignancy, myeloablative allogeneic hematopoietic cell transplantation

Brief summary

This is a randomized, multisite, Phase II study designed to compare the 1-year GVHD-free survival of the control arm (no axatilimab) to the experimental arm (axatilimab) after myeloablative allogeneic HCT.

Detailed description

This study will determine if axatilimab in combination with standard of care posttransplant cyclophosphamide + tacrolimus/mycophenolate mofetil is safe, tolerable, and efficacious as GVHD prophylaxis in a population of adult patients with hematologic malignancies receiving a first HLA-matched related or unrelated donor myeloablative allogeneic HCT.

Interventions

PROCEDUREHematopoietic Cell Transplantation

Subjects will receive a first HLA-matched related or (7/8 or 8/8) unrelated donor myeloablative allogeneic HCT.

DRUGCyclophosphamide

Cyclophosphamide will be given on Day +3 and Day +4 per institutional practices, at a dose of 50 mg/kg IBW. Cyclophosphamide will be given as an IV infusion over 1-2 hours (depending on volume), or according to institutional standards.

DRUGTacrolimus

Tacrolimus will be given per institutional practices, starting on Day +5. Subsequent dosing will be based on blood levels per institutional guidelines with a suggested range of 5-12 ng/mL.

DRUGMycophenolate Mofetil (MMF)

Mycophenolate mofetil (MMF) will be given per institutional practices, at a dose of 15 mg/kg three times daily (TID; based upon actual body weight) with the maximum total daily dose not to exceed 3 grams (1g TID, IV or PO). MMF prophylaxis will start Day +5 and continue until Day +35 post-transplant, at which time it should be discontinued (no taper necessary).

DRUGAxatilimab

The dose is dependent on the results of the safety run-in. The starting dose of the safety run-in is 0.3 mg/kg (maximum of 35 mg). If Dose Level 1 has an unacceptable level of toxicity (≥2 patients having significant toxicity), then axatilimab may be de-escalated to 0.2 mg/kg (maximum of 23 mg).

Sponsors

Medical College of Wisconsin
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Age ≥18 years. * Patients with a history of a hematologic malignancy with a planned myeloablative conditioning (MAC) peripheral blood allogeneic HCT. a. Note: Patients with acute leukemia must be in morphologic complete remission with or without hematologic recovery with ≤5% blasts in the bone marrow. Patients with Chronic Myelomonocytic Leukemia (CMML) must have a white blood cell (WBC) count ≤10,000 cells/µL and ≤5% blasts in the marrow. Patients with ≥5% blasts due to a regenerating marrow must contact the protocol chairs for review. Patients with a diagnosis of myelofibrosis require sponsor approval before enrolling. * Patients must be receiving an allograft from a suitable HLA-matched sibling or (7/8 or 8/8) unrelated donor according to transplant center's guidelines (for selection of appropriate donor). * The following laboratory values obtained ≤14 days prior to registration/randomization: 1. Total bilirubin ≤1.5 x ULN or total bilirubin ≤3.0 x the Upper Limit of Normal (ULN) in the presence of Gilbert's syndrome. If total bilirubin is abnormal (≥1.5 x ULN), assess direct bilirubin. NOTE: Patients with Gilbert Syndrome and elevated baseline unconjugated (indirect) bilirubin up to 3.0 mg/dL are eligible. Gilbert syndrome should be confirmed by the presence of UGT1A1\*28 variant. 2. Alanine aminotransferase (ALT) and aspartate transaminase (AST) ≤2.5 x ULN). 3. Calculated creatinine clearance ≥30 mL/min using the Cockcroft-Gault formula below: Creatinine clearance for males = (140 - age)(weight in kg) /(72)(serum creatinine in mg⁄dL) Creatinine clearance for females = (140 - age)(weight in kg) (0.85) /(72)(serum creatinine in mg⁄dL) * Negative serum pregnancy test done ≤7 days prior to registration/randomization, for persons of childbearing potential only. * Sexually active patients and their partners must use an effective method of contraception associated with a low failure rate prior to study entry and for the duration of study participation and for at least 3 months after the last dose of study drug. a. Note: The following are considered effective contraceptives: oral contraceptive pill; condom plus spermicide; diaphragm plus spermicide; patient or partner surgically sterile; patient or partner more than 12 months postmenopausal; or injectable or implantable agent/device. Male patients should refrain from sperm donation and female patients should refrain from breastfeeding throughout this period. * Ability to understand and provide written informed consent at the time of initial study enrollment. Participants who later lose decisional capacity may remain on study with consent from a legally authorized representative (LAR), as applicable. * Willingness to provide mandatory blood and bone marrow aspirate specimens for correlative research. * Willing to return to enrolling institution for follow-up (during the Active Monitoring Phase of the study).

Exclusion criteria

* Any of the following because this study involves an investigational agent whose genotoxic, mutagenic, and teratogenic effect on the developing fetus and newborn are unknown: 1. Pregnant persons. 2. Nursing persons. 3. Persons of childbearing potential, and persons able to father a child, who are unwilling to employ adequate contraception. * Any of the following current or prior therapies: 1. Patients receiving a cord blood transplant. 2. Patients undergoing a T-cell depleted allogeneic transplantation (using ex vivo CD34 selection, or with serotherapy \[antithymocyte globulin or alemtuzumab\]). 3. Patients undergoing a second allogeneic transplant (after a previous allogeneic transplant). 4. Pre-planned treatment with JAK1/JAK2 inhibitor after transplant. 5. Previous exposure to axatilimab. 6. Receiving an investigational treatment ≤28 days prior to registration/randomization. 7. Major surgery ≤3 weeks prior to registration/randomization. 8. Chemotherapy ≤2 weeks prior to registration/randomization unless chemotherapy is part of the pre-transplant conditioning. 9. Radiation therapy ≤2 weeks prior to registration/randomization unless radiation is part of the pre-transplant conditioning. 10. Planned use of Donor Lymphocyte Infusion (DLI) therapy. 11. Exception: Use of maintenance regimens as routine clinical care will be permitted but must be declared prior to registration/randomization. The trial does not restrict subsequent treatment after meeting the GFS endpoint. * Active central nervous system (CNS) involvement by malignant cells. * Leukemia involvement in the CNS ≤4 weeks of registration for patients with a history of prior CNS leukemia involvement (i.e., leukemic blasts previously detected in the cerebral spinal fluid). * History of acute or chronic pancreatitis. * History of myositis. * Co-morbid systemic illnesses or other severe concurrent disease which, in the judgment of the investigator, would make the patient inappropriate for entry into this study or interfere significantly with the proper assessment of safety and toxicity of the prescribed regimens. * Patients with active hepatitis B or C. a. Patients with a history of hepatitis B or C are allowed if HBV DNA or HCV RNA are undetectable. * Any known infection with human immunodeficiency virus (HIV), HTLV-1. * Uncontrolled bacterial, viral, or fungal infections (currently taking medication and with progression or no clinical improvement) at the time of registration/randomization. * Psychiatric illness/social situations that would limit compliance with study requirements. * Diagnosed with another malignancy (other than malignancy for which transplant was performed) ≤ 3 years of registration/randomization, unless previously treated with curative intent and approved by PI (e.g., but not limited to completely resected basal cell, squamous cell, or ductal carcinoma in situ, or low-risk prostate cancer after curative resection or on watchful waiting). In patients with transformed disease (e.g. aggressive lymphoma evolving from CLL, or acute leukemia from MDS), the original hematological disorder is not considered an exclusion. Cancer treated with curative intent \<3 years previously will not be allowed unless approved by any of the Study Chairs. * History of myocardial infarction ≤6 months, or New York Heart Association (NYHA) Class III or IV heart failure, uncontrolled angina, severe uncontrolled ventricular arrhythmias, or electrocardiographic evidence of acute ischemia.

Design outcomes

Primary

MeasureTime frameDescription
GVHD-free survival1 Year Post HCTA patient will be considered a success for 1-year GVHD-free survival if they are alive without Grade 3 or 4 acute GVHD or systemic immunosuppression requiring chronic GVHD at one year post transplant. Death, Grade 3 or 4 acute GVHD, and immunosuppression-requiring chronic GVHD (of any severity) prior to 1 year will be considered as events.

Countries

United States

Contacts

CONTACTMedical College of Wisconsin Cancer Center Clinical Trials Office
cccto@mcw.edu866-680-0505
STUDY_CHAIRMehdi Hamadani, MD

Medical College of Wisconsin

PRINCIPAL_INVESTIGATORSameem Abedin, MD

Medical College of Wisconsin

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Sep 9, 2026