Haploidentical Transplant for People With Chronic Granulomatous Disease Using Post Transplant Cyclophosphamide

Background: \- Chronic Granulomatous Disease (CGD) causes immune system problems. Treatment is usually a bone marrow transplant from a fully matched donor. Researchers want to try using partially matched donors for patients who do not have a fully matched donor available. The researchers will also use the drug cyclophosphamide to try to improve the outcomes when using a partially matched donor. Objective: \- To learn the effectiveness of using cyclophosphamide with a transplant from a partially matched donor in treating CGD. Eligibility: \- Recipients: age 2-65 with CGD with an ongoing infection that has not been cured by standard treatment and no fully matched donor available in an appropriate timeframe. Design: * Recipients will: * be admitted to the hospital 2 weeks before transplant. * be screened with blood and urine tests, breathing and heart health tests, X-rays, and/or magnetic resonance imaging. They may have a bone marrow aspiration and biopsy. * meet with a social worker and dentist. * get chemotherapy, radiation, and other medicines. * get an intravenous (IV) catheter in their chest. * have the transplant. * get more medicines and standard supportive care. * have blood drawn frequently. * have to stay in the Washington, D.C. area for 3 months post-transplant. * be followed closely for the first 6 months, and then less frequently for at least 5 years.

Allogeneic transplant using HLA matched donors, both related and unrelated, has proven curative for patients with various immunodeficiencies, including those with ongoing infections. However donor availability remains a limiting factor in the application of this treatment modality. The use of haploidentical donors has in the past been fraught with a greater rate of complications related to both higher rates of GvHD and delayed immunorecovery. Newer transplant regimens appear to have diminished these risks and improved outcomes. We propose using a subablative conditioning regimen followed by post-transplant cyclophosphamide for patients with CGD who do not have an HLA matched donor but whose circumstances necessitate the use of a potentially curative, albeit high-risk treatment modality.