The Diamyd vaccine is currently being tested as a means to slow or stop the progression of type 1 diabetes in recently diagnosed patients, age 10 to 20 years. Reference 1 describes two phase-3 trials in progress, one in the United States and one in Europe. Results from phase-2 trials are encouraging.
Type 1 diabetes is generally considered to be an autoimmune disorder which destroys the insulin-secreting beta cells of the pancreas. In rare cases, patients go into complete remission shortly after diagnosis. Partial remission is more common, and many patients are able to produce some insulin for considerable time periods after diagnosis. This residual insulin secretion is of great importance, since it reduces blood glucose fluctuations and the risk of complications.
Over the last three decades, research into immune modulation therapy for type 1 diabetes has shown promising results. Cyclosporin, the immunosuppressive drug best known for organ transplant therapy, demonstrated significant preservation of insulin secretion. Unfortunately, the side effects were considered worse than the original condition of type 1 diabetes. Other immune intervention therapies have been tried, including azathioprine, linomide, antithymocyte globulin, prednisone, antioxidants, immunoglobulins, photopheresis, and plasmapheresis. The risks were judged to be greater than the benefits, but the studies led to further ideas for therapy.
Early studies on plasmapheresis uncovered a variant form of glutamic acid decarboxylase (GAD) in the blood of children with diabetes. Autoantibodies to GAD have been identified as antigens for autoimmune diabetes. The Diamyd vaccine was developed to modulate the immune response to GAD, with the goal of preserving beta cell function and insulin secretion.
For children at risk for type 1 diabetes, the vaccine is being tested in Europe as a preventive measure. Similar trials are under discussion for the United States.
Type 1 diabetes was once called juvenile onset diabetes, but it is now recognized that adults of any age can develop this condition.