A new form of treatment for type 1 diabetes that's based on the immune system appears safe for patients in an early trial.
However, only a larger trial will show if the treatment – which uses immune cells called regulatory T cells (Tregs) – is effective against the illness, researchers said.
A new way forward
If the therapy does work out, it "could be a game-changer", study first author Jeffrey Bluestone, a professor of metabolism and endocrinology at the University of California, San Francisco, said in a university news release.
"For type 1 diabetes, we've traditionally given immunosuppressive drugs, but this trial gives us a new way forward. By using Tregs to 're-educate' the immune system, we may be able to really change the course of this disease," he explained.
Read: T cells
In type 1 diabetes, the immune system attacks insulin-secreting beta cells in the pancreas. Many treatments suppress the immune system, but that can lead to serious side effects, such as increasing a patient's susceptibility to infections or cancer. About 5 percent of all cases of diabetes are type 1 disease.
According to the researchers, the new therapy uses a patient's own regulatory T cells to protect insulin-producing beta cells in the pancreas. The approach is designed to reduce the immune system's attack on beta cells, while still leaving the immune system strong enough to fight infections.
The patients in the first U.S. safety trial of the treatment received infusions of as many as 2.6 billion of the protective Treg cells and had no serious side effects, Bluestone's team said.
The results of the Phase 1 trial were published online in the journal Science Translational Medicine. Phase 1 trials typically only examine if a drug or intervention is safe, they are not focused on effectiveness.
A very novel approach
The next phase of this research would be a clinical trial to test the effectiveness of the new therapy, the researchers said.
Two experts in type 1 diabetes said the approach holds real promise.
"This is a very novel approach to treatment because it deals with the route cause for type 1 diabetes – which is destruction of the insulin-producing cells of the pancreas by one's own immune system," said Dr Deena Adimoolam, assistant professor of medicine, endocrinology, diabetes and bone disease at the Icahn School of Medicine at Mount Sinai in New York City.
"The use of regulatory T-cells in its early stages of clinical research appears successful," she said, "and I hope that future trials show long-term treatment with minimal side effects."
Dr Minisha Sood directs inpatient diabetes care at Lenox Hill Hospital, also in New York City. She said that regulatory T cells "are known to control autoimmunity – not only in type 1 diabetes but also in a number of other autoimmune diseases. Therefore, it is believed that eventual treatments involving regulatory T cells may slow progression of or reverse the autoimmunity, which is the cause of type 1 diabetes."
While larger trials are needed to confirm a benefit for patients, the study "did establish that immunotherapy with regulatory T cells is feasible from a safety standpoint, which is very promising", Sood said.