(BMT CTN 1204) Reduced-Intensity Conditioning for Children and Adults with Hemophagocytic Syndromes or Selected Primary Immune Deficiencies (RICHI)
HLH, HLH-related disorders, Chronic Granulomatous (CGD), HIGM1, Immune dysregulation, polyendocrinopathy, enteropathy, and X-linked inheritance (IPEX) and severe LAD-I represent primary immune disorders that are typically fatal without Hematopoietic Cell Transplant (HCT). However, transplant is often complicated by inflammation, infection and other co-morbidities. In addition, these disorders have been shown to be cured with partial chimerism, making them an ideal target for the use of reduced intensity approaches, where a portion of patients may not achieve full donor chimerism, but instead achieve stable mixed chimerism. Reduced-intensity conditioning strategies have demonstrated improved survival with decreased Treatment Related Mortality (TRM) in institutional series for patients with HLH (Cooper et al., 2006; Marsh et al., 2010; Marsh et al., 2011). However, graft loss and unstable chimerism remain challenges. An institutional case series from Cincinnati Children's Hospital demonstrated full or high-level chimerism and improved durable engraftment using intermediate (Day -14) timing alemtuzumab (Marsh et al., 2013b). This study aims to test the efficacy of the Intermediate RIC strategy in a prospective multi-center study including HLH as well as other primary immunodeficiencies where allogeneic transplant with RIC has been shown to be feasible and stable chimerism is curative.