A new study reports that the majority of patients with type 1 diabetes who underwent a certain type of stem cell transplantation became insulin-free, several for more than 3 years, with good glycemic control, and also increased C-peptide levels, an indirect measure of beta-cell function. Richard K. Burt, MD, of the Northwestern University Feinberg School of Medicine, Chicago, presented the findings of the study at a Journal of the American Medical Association (JAMA) media briefing at the National Press Club in Washington, DC. Clinical evidence indicates that there is an inverse association between beta-cell (a type of cell in the pancreas that secretes insulin) preservation and function and chro-nic complications of type 1 diabetes mellitus (DM); the higher the C-peptide levels (a byproduct of insulin production, made up of amino acids), the lower the incidence of some types of complications of type 1 DM. A previous study found that autologous nonmyeloablative hematopoietic stem cell transplantation (HSCT) in 15 patients with newly diagnosed type 1 DM resulted in the majority of patients becoming insulin-free during the follow-up, which averaged about 19 months. “However, it was suggested that subsequent insulin inde-pendence was a prolonged honeymoon period due to dietary and exercise changes associated with close post transplant medical observation,” the authors write, and it was not known if this change was because of an improvement in beta-cell pre-servation. HSCT, which uses a patient’s own blood stem cells, involves the removal and treatment of the stem cells, and their return to the patient by intravenous injection. Dr. Burt, et al conducted a study to determine if post transplant insulin independence was due to im-proved beta-cell function by monitoring the C-peptide levels of 23 patients who underwent stem cell transplantation. The patients, with type 1 DM, were ages 13 to 31 years. Of the 23 patients, 20 experienced time free from insulin (12 continuously and 8 transiently). Patients remained continuously insulin-free for an average time of 31 months (range, 14 to 52 months). One patient had more than 4 years with no exogenous insulin use, 4 patients for at least 3 years, 3 patients for at least 2 years, and 4 patients for at least 1 year. Eight patients relapsed and resumed insulin use at low doses. The majority of patients achieved good glycemic control. “In conclusion, autologous nonmyeloablative HSCT was able to induce prolonged and significant increases of C-peptide levels associated with absence of or reduction of daily insulin doses in a small group of patients with type 1 DM,” the researchers write. “At the present time, autologous nonmyeloablative HSCT remains the only treatment capable of reversing type 1 DM in humans. Randomized controlled trials and further biological studies are necessary to confirm the role of this treatment in changing the natural history of type 1 DM.”
(Source: Diabetes In Control, Issue 466, April 28, 2009; original source: JAMA.2009;301[15]:1573-1579.)
