Approved Drug may Slow Type 1 Diabetes
Reported December 09, 2009
(Ivanhoe Newswire) — A drug already used to treat autoimmune disorders may also slow the destruction of insulin-producing cells in patients with insulin-dependent (type 1) diabetes.
In type 1 diabetes, formerly known as juvenile diabetes, insulin-producing beta cells in the pancreas are destroyed by an autoimmune process.
Researchers at UT Southwestern and 14 other centers worldwide found that injections of the drug rituximab slowed beta cell destruction for at least a year in the pancreas of those newly diagnosed with type 1 diabetes, suggesting a potential treatment option to improve management and reduce long-term complications of the disease.
Dr. Philip Raskin, professor of internal medicine at UT Southwestern, called the findings extremely exciting. “Our findings in no way suggest that rituximab should be used as a treatment or that it will eliminate the need for daily insulin injections,” Dr. Raskin, principal investigator of the trial’s local effort, was quoted as saying. “This is not a cure for type 1 diabetes.
Dr. Raskin went on the explain, “The results do, however, provide evidence that B cells play a significant role in type 1 diabetes, and that selective suppression of these B cells may deter the destruction of the body’s beta cells.”
Prior research has shown that two types of immune cells — B cells and T cells — help trigger type 1 diabetes. T cells attack and destroy the insulin-producing beta cells. The B cells, however, don’t directly attack insulin-producing cells, but researchers have speculated that they trigger the T cells to attack. Rituximab directly attacks and destroys the B cells.
Researchers conducted a study in which 81 participants received infusions of either rituximab or a placebo once a week for four weeks. The participants ranged in age from 8 to 40 years old and had been diagnosed with type 1 diabetes within 100 days of enrollment in the study. They returned approximately every three months for two years to undergo blood tests and meet with a physician. Two-thirds of the 81 participants received the drug.
After one year, the participants who received rituximab needed lower doses of insulin and were able to produce more of their own insulin than those who received the placebo. They also had better control of their blood sugar.
Dr. Raskin said researchers do not think rituximab could ever be used to completely reverse type 1 diabetes because the pancreas typically is too damaged by the time diabetes is diagnosed.
He also said that while the exact mechanism of how rituximab affects type 1 diabetes remains unclear, the study clearly shows that a therapy that targets B cells may improve beta-cell function in early type 1 diabetes.
SOURCE: New England Journal of Medicine, December 4, 2009
