Diabetes vaccine shows promise for some patients in early trial

Doctor samples the blood of a patient with diabetes.
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In a small, early study, a vaccine for type 1 diabetes helped preserve the body's natural production of insulin, at least in a subset of newly diagnosed patients.

In patients with type 1 diabetes, the body's immune system attacks the beta cells in the pancreas that produce insulin, a hormone that's necessary for cells to absorb glucose from the bloodstream. These patients need lifelong insulin injections to stay alive. 

"Studies have shown that even an extremely small production of insulin in the body is highly beneficial for patient health," lead author Dr. Johnny Ludvigsson, a senior professor in the Department of Biomedical and Clinical Sciences at Linköping University in Sweden, said in a statement. "People with diabetes who produce a certain amount of insulin naturally do not develop low blood sugar levels, hypoglycemia, so easily."

People with certain versions of immune system genes, known as human leukocyte antigen (HLA) genes, are at higher risk of developing type 1 diabetes. Several HLA types increase the risk of the autoimmune disorder, but one genetic variant, known as "HLA-DR3-DQ2," exposes a form of the GAD protein (GAD65) to the immune system on the surface of beta cells, according to the statement. This triggers the immune system to produce antibodies against the protein and target the beta cells for destruction. 

The researchers wanted to see if a vaccine that exposed the body to more GAD would help the immune system better tolerate the body's natural GAD65 and thus stop attacking the insulin-producing cells.

For the phase 2 clinical study, the researchers recruited 109 patients between the ages of 12 and 24 who had been diagnosed with type 1 diabetes within the past six months. About half of the patients carried the  HLA-DR3-DQ2 gene variant. 

The researchers divided the participants into two groups: Half of the participants, assigned randomly, were given three shots of the vaccine into their lymph nodes, each one month apart, and the other half were given a placebo. 

As a whole, there was no difference in the treatment and placebo groups. But the subset of patients who had the HLA-DR3-DQ2 variant did not lose insulin production as quickly as other patients did. 

"Treatment with GAD-alum seems to be a promising, simple and safe way to preserve insulin production in around half of patients with type 1 diabetes, the ones who have the right type of HLA," Ludvigsson said. "This is why we are looking forward to carrying out larger studies, and we hope these will lead to a drug that can change the progress of type 1 diabetes."

The study, published online May 21 in the journal Diabetes Care, was funded by the pharmaceutical company Diamyd Medical AB, which was also involved in planning and collecting data in the trial, the Swedish Child Diabetes Foundation and the Swedish Diabetes Foundation.

Originally published on Live Science.

Yasemin Saplakoglu
Staff Writer

Yasemin is a staff writer at Live Science, covering health, neuroscience and biology. Her work has appeared in Scientific American, Science and the San Jose Mercury News. She has a bachelor's degree in biomedical engineering from the University of Connecticut and a graduate certificate in science communication from the University of California, Santa Cruz.