Experimental drug can modulate onset
Type 1 diabetes destroys the beta cells in the pancreas that make and release insulin. According to the American Diabetes Association, about 1.25 million people in the U.S. have the disease, and almost 18,000 new cases are diagnosed annually in people under age 20.
In a clinical trial financed by the National Institutes of Health and the Juvenile Diabetes Research Foundation, Provention Bio Inc.’s experimental drug teplizumab delayed the development of type 1 diabetes by one year or more in people at high risk for the disease. The study findings were revealed at a meeting of the American Diabetes Association in San Francisco and in The New England Journal of Medicine.
The clinical trial entailed 14 days of therapy with the experimental drug. There were 76 study participants, selected because they faced a high risk of type 1 diabetes in part because their relatives had the autoimmune disease. Participants, ranging in age from 8 to 49, underwent tests that showed diabetes-related autoantibodies that attack the pancreas, plus unhealthy blood sugar levels.
Of the 44 trial participants who were randomly assigned to receive the drug, 19 (43 percent) developed diabetes. The disease appeared within 48.4 months in half of these participants. Of the 32 people who received a placebo, 23 (72 percent) developed diabetes. The disease developed in half of the patients within 24.4 months. At the end of the study the percentage of diabetes-free participants was twice as high in the teplizumab group (57 percent) as in the placebo group (28 percent). Reported side effects included temporarily low levels of lymphocytes and rash.
Teplizumab’s method of action is to modify the white blood cells from the immune system that kill insulin-producing cells in the pancreas. Its greatest impact appeared to be in the first year after treatment. In that time frame, only 7 percent of the participants developed type 1 diabetes, as compared with 44 percent who received the placebo.
Dr. Kevan Herold of Yale University in New Haven, Connecticut, said, "After repeated failures, this is the first time anyone's been able to delay the onset of type 1 diabetes. The rate of development of diabetes was reduced by half."
Dr. Clifford Rosen of the Maine Medical Center Research Institute and Journal deputy editor Dr. Julie Ingelfinger added, "We can finally say that there has been substantial progress in modulating the early course of type 1 diabetes."
Another round of therapy might further delay diabetes development and "that's what we're hoping to do," said Herold, who thought there would be reluctance to give the drug long-term for fear it might throttle back the immune system too much. He added,
"It's been felt that to have a really effective treatment, you need a drug you give for a short period of time, so people are not chronically immunosuppressed."
Many new drugs come with a price of more than $100,000 per year. If teplizumab were to delay development of type 1 diabetes for about a year, people might deem it worthwhile, Herold said.
More studies will be needed before regulatory agencies will be able to approve the drug.