A Phase II Study of Allogeneic Hematopoietic Stem Cell Transplant for Subjects With VEXAS (Vacuoles, E1 Enzyme, X-linked, Autoinflammatory, Somatic) Syndrome

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....