Recruiting
Phase 2

Stem Cell Transplant

Sponsor:

National Cancer Institute (NCI)

Code:

NCT05027945

Conditions

Immunodeficiency

Hematopoietic Stem Cell Transplantation

Eligibility Criteria

Sex: All

Age: 18 - 70+

Healthy Volunteers: Not accepted

Interventions

Allogeneic HSCT

Busulfan test dose

Mycophenolate mofetil (MMF)

Tacrolimus

Busulfan

Study Details

Brief summary:

Background:

Allogeneic hematopoietic stem cell transplant involves taking blood stem cells from a donor and giving them to a recipient. The transplants are used to treat certain diseases and cancers. Researchers want to see if the transplant can treat VEXAS Syndrome.

Objective:

To see if stem cell transplants can be successfully performed in people with VEXAS and even improve the disease.

Eligibility:

People ages 18-75 who have VEXAS Syndrome that has caused significant health problems and standard treatment either has not worked or is not available.

Design:

Participants will be screened with:

Physical exam

Medical review

Blood and urine tests

Heart and lung function tests

Bone marrow biopsy

Participants will have a chest x-ray. They will have an imaging scan of the head, chest, abdomen, pelvis, and sinus. They will have a bone density scan. They will have a dental exam and eye exam. They will meet with specialists. They will repeat some screening tests.

Participants will be admitted to the NIH hospital. They have a central venous catheter put into a vein in the chest or neck. They will receive drugs to prepare their bone marrow for the transplant. They may have total body irradiation. They will receive the donor stem cells through the catheter. They will get other drugs to prevent complications and infections. After discharge, they must stay in the DC area for 3 months for weekly study visits.

Participants will have study visits 30, 60, 100, 180, 210, 240, 300, and 360 days later. After that, they will have yearly visits for 2 years and then be contacted yearly by phone....

Conditions

Immunodeficiency

Hematopoietic Stem Cell Transplantation

Study ID

NCT05027945

Start date

Feb 23, 2023

Status verified date

Jul 8, 2026

Completion date

Jul 1, 2031

Anticipated

Primary completion date

Jul 1, 2031

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 70+

Healthy Volunteers: Not accepted

  • INCLUSION CRITERIA:

Non-disease related

  • Age >= 18-year-old and <= 75-year-old
  • Availability of an 8/8 or 7/8 HLA-matched related or unrelated donor, or a haploidentical related donor
  • Karnofsky performance status of >= 40%
  • Adequate end-organ function, defined as follow:

1. Left ventricular ejection fraction > 35%, preferably by 2-D echocardiogram (ECHO) obtained within 60 days prior to treatment initiation.
2. Creatinine <= 2.0 mg/dl and creatinine clearance >= 30 ml/min;
3. Serum conjugated bilirubin < 3.0 mg/dl; serum ALT and AST <= 5 times upper limit of normal.
  • Pulmonary function tests: FEV1 and DLCO >30%
  • Ability of subject to understand and the willingness to sign a written informed consent document.
  • As therapeutic agents used in this trial may be harmful to a fetus, individuals of childbearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) at the study entry and for at least one-year post-allo HCT. Should an individual become pregnant or suspect they are pregnant while she or her partner is participating in the study, she should inform her treating physician immediately.
  • Willingness to remain in the NIH hospital or, if discharged, live within 2 hours drive from the NIH, for a minimum of 100 days after transplant or longer, if there are complications. If outpatient in the first 100 days after transplant, participant must commit to having an adult caregiver with them at all times.

Disease related

  • Somatic mutation in UBA1 performed by a CLIA or CAP certified laboratory. NOTE: Participants without a mutation or unknown mutation status may be eligible if they have a clinical history that is characteristic of an individual with VEXAS syndrome including two or more of a-e below.
  • Inflammatory clinical phenotype for VEXAS syndrome with at least one VEXAS disease manifestation below:

1. constitutional symptoms including fevers, fatigue, and weight loss
2. cutaneous symptoms of VEXAS including biopsy proven neutrophilic dermatosis, cutaneous vasculitis, periorbital inflammation
3. pulmonary symptoms of VEXAS with pulmonary infiltrates, pleural effusion
4. musculoskeletal or cartilaginous involvement including inflammatory arthritis, ear chondritis, and nasal chondritis
5. inflammatory disease in other major organ systems including cardiac, gastrointestinal, ocular, etc.
  • Presence of cytopenia defined as at least one of the following:

i. Absolute neutrophil count <=1000/ microliter

ii. platelet count <= 75,000/microliter or platelet transfusion dependence (at least 4 platelet transfusions in the 8 weeks prior to study entry

iii. hemoglobin <= 10.0g/dL or red cell transfusion-dependence (at least 4 units of PRBCs in the 8 weeks prior to treatment initiation) or meeting criteria for myeloid neoplasm (MN) by updated 2022 WHO criteria or 2022 International Consensus Classification (ICC) of myeloid neoplasms and acute leukemia

OR:

-Participants who have failed standard medical management (requiring >= 0.5mg/kg per day of prednisone for the above listed inflammatory condition or intolerance or refractory to use of corticosteroids and/or steroid sparing medications as well as biological response modifiers over the last 6 months), or when no standard medical treatment is available.

EXCLUSION CRITERIA:

  • HCT Comorbidity Index >= 5. Note: Comorbidities that are specifically addressed in the inclusion criteria will not be included in the calculation of HCT-CI score.
  • Participants with multiple myeloma. Note: participants with low risk smoldering multiple myeloma or monoclonal gammopathy of unknown significance will not be excluded)
  • Participants who are receiving any other investigational agents within the last 30 days before treatment initiation.
  • HIV-positive patients are ineligible because these patients are at increased risk of lethal infections when treated with marrow-suppressive therapy.
  • History of allergic reactions attributed to compounds of similar chemical or biologic composition to agents (steroids, cyclophosphamide, busulfan, tacrolimus, MMF, filgrastim or filgrastim biosimilar) used in the study.
  • Pregnant individuals are excluded from this study because the study agents have the potential for teratogenic or abortifacient effects. Because there is an unknown but potential risk for adverse events in nursing infants secondary to treatment of the mother with the study agents, breastfeeding should be discontinued if the mother is treated with the study agents.
  • Uncontrolled intercurrent illness or social situations (as determined by a licensed master social worker) that would limit compliance with study requirements.
  • Presence of active uncontrolled infections that in the opinion of the PI would make it unsafe to proceed with transplantation.
  • Active psychiatric disorder which is deemed by the PI to have significant risk of compromising compliance with the transplant protocol.

Study Design

Enrollment

54 participants

Anticipated

Allocation

Non randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Arm A

Reduced intensity regimen (Fludarabine, busulfan)+HSCT+GVHD prophylaxis

experimental: Arm B

Reduced intensity regimen (Fludarabine, low dose cyclophosphamide, 200cGY TBI, busulfan)+HSCT+GVHD prophylaxis

Interventions

Allogeneic HSCT

stem cell transplant on day 0

Busulfan test dose

0.8 mg/kg IV over 2 hours. May be skipped if real-time PKs are done during conditioning.

Mycophenolate mofetil (MMF)

Mycophenolate mofetil (MMF): 15 mg/kg IV over 2 hours BID starting on day +5 until approximately day +35 (+/-2 days)

Tacrolimus

Starting on day +5, start at 0.02 mg/kg IV continuous infusion over 24 hours until day +180 and titrated to trough levels of 5-15 mg/ml.

Busulfan

AUC Targeted Dose based on busulfan test dose PKs, IV infusion over 3 hours once daily (3.2 mg/kg IV per day will be the default dose) per the below time frame: For 8/8 Matched Related or Unrelated Donor Busulfan dose will be on days -6, -5, and -4 For 7/8 Matched Related or Unrelated or Haploidentical Donor Busulfan dose will be on days -4 and -3

Total Body Irradiation (TBI)

For 7/8 Matched Related or Unrelated or Haploidentical Donor, 200cGy on day -1

Fludarabine

40 mg/m2 IV over 30 mins daily For 8/8 Matched Related or Unrelated Donor Fludarabine dose will be on days -6, -5, -4, and -3 For 7/8 Matched Related or Unrelated or Haploidentical Donor Fludarabine dose will be on days -6, -5, -4, -3, and -2

Cyclophosphamide (CY)

For 7/8 Matched Related or Unrelated or Haploidentical Donor, prior to transplant 14.5 mg/kg IV daily on days -6 and -5

Post-Transplant Cyclophosphamide (PTCY)

Post-Transplant Cyclophosphamide: 50 mg/kg IV daily over 2 hours on days +3 and +4, dosed according to ideal body weight

Primary outcome measure

  • Reversal of clinical phenotype of VEXAS [ Time Frame: +1 and +2 years post HSCT ]
  • Sustained donor engraftment [ Time Frame: day +100 and +1 year post HSCT ]

Central Contacts and Locations

Central contacts

Locations

National Institutes of Health Clinical Center

Recruiting

Bethesda, Maryland, United States, 20892

Contacts

For more information at the NIH Clinical Center contact National Cancer Institute Referral Office

888-624-1937

More Information

Sponsor

National Cancer Institute (NCI)

Last update posted

Jul 10, 2026

Last verified

Jul 8, 2026

Keywords

  • Immune Dysregulation
  • Haploidentical
  • hematoinflammatory diseases
  • Myelodysplastic Syndromes
  • Autoimmune Disorders

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by National Cancer Institute (NCI) on 2026-07-10.