Stem cell transplantation for CD has been recognized as a potential therapeutic modality since the 1980s. Northwestern University treated 24 patients with CD where stem cells were mobilized with cyclophosphamide 2 mg/m2 and G-CSF 10 mcg/kg/day followed by an immunoablative transplant using cyclophosphamide 200 mg/kg (50 mg/kg daily for 4 days) and ATG (30 mg/kg) as per the previously referenced consensus statement by EBMT. In this study there was no treatment related mortality and clinical relapse-free survival (defined as not restarting CD therapy) was 73% (17/23) at 1 year but declined to 19% at 5 years demonstrating the problem of durable disease control with autologous transplant alone. Interestingly, 8/15 (53%) patients who restarted therapy for recurrent Crohn's symptoms were able to achieve clinical remission, highlighting the possibility that efficacy of medications previously used can be restored following autologous HSCT. Autologous Stem-Cell Transplantation in Crohn's Disease (ASTIC) trial randomized patients either to autologous transplantation or stem cell mobilization chemotherapy without transplantation. This trial design allowed for the benefit of autologous HCT to be assessed independently of the potential benefit of the immunosuppression from high dose cyclophosphamide used to mobilize stem cells. The primary endpoint of the trial was assessed by the Crohn's Disease Activity Index (CDAI), the most prevalent method of assessing Crohn's disease clinical activity, where a level <150 is considered to represent disease remission. The ASTIC trial demonstrated at 1 year in patients who underwent transplant 44% were in clinical remission compared to 9% of patients who underwent mobilization only (p = 0.017). One death occurred in this study believed secondary to cyclophosphamide induced sinusoidal obstructive syndrome. Across all studies there has been one treatment related death out of 69 transplanted patients (1%), which is approximately the rate expected with autologous HCT for a malignancy such as multiple myeloma and significantly lower than the 5-10% expected transplant related mortality for other malignancies like lymphoma. Additional support for the safety of autologous HCT for autoimmune disorders comes from similarly designed studies using the same conditioning regimen of cyclophosphamide and ATG for other autoimmune or connective tissue disorders. For example, the one year mortality rate following autologous transplantation in 129 relapsing-remitting multiple sclerosis patients was 0%.