(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
