Hematopoietic stem cell transplantation (HSCT), compared to the use of chemotherapeutic drugs was thought to increase the risk of death among patients with a severe form of sclerosis, a study has found.
Systemic sclerosis is an autoimmune connective tissue disease characterized by vasculopathy (a disorder of the blood vessels), low-grade inflammation, and fibrosis (development of excess fibrous connective tissue) in skin and internal organs. Previously, small studies have shown that systemic sclerosis is responsive to treatment with autologous HSCT, although it has been unclear whether HSCT improves survival, according to background information in the article. For this study, autologous HSCT involved a multistep process beginning with infusion of high doses of cyclophosphamide and an antibody against immune cells, followed by reinfusion of the patient's own stem cells that had been previously collected from blood and purified.
Jacob M. van Laar, M.D., Ph.D., of the University Medical Center Utrecht, Utrecht, the Netherlands and Dominique Farge M.D., Ph.D, of the Assistance Publique - Hopitaux de Paris, Paris 7 Diderot University, France, and colleagues randomly assigned 156 patients with early diffuse cutaneous (widespread skin involvement) systemic sclerosis to receive HSCT (n = 79) or cyclophosphamide (n = 77; 12 monthly infusions). The phase 3 clinical trial was conducted in 10 countries at 29 centers; patients were recruited from March 2001 to October 2009 and followed up until October 2013.
Patients in the HCST group experienced higher mortality in the first year but had better long-term overall survival than those treated with cyclophosphamide. During year 1 there were 11 deaths (13.9 percent, including 8 treatment-related deaths) in the HSCT group vs 7 (9.1 percent, no treatment-related deaths) in the control group. After year 2 of follow-up, there were 12 deaths (15.2 percent) in the HSCT group vs 13 (16.9 percent) in the control group. After 4 years of follow-up, there were 13 deaths (16.5 percent) in the HSCT group vs 20 (26.0 percent) in the control group.
The authors add that HSCT was also more effective than intravenous cyclophosphamide on measures evaluating skin, functional ability, quality of life, and lung function, consistent with previous studies.
"Among patients with early diffuse cutaneous systemic sclerosis, HSCT was associated with increased treatment-related mortality in the first year after treatment. However, HCST conferred a significant long-term event-free survival benefit," the authors conclude.