Insulin, in the form of pills failed to delay or prevent the the development of type 1 diabetes among relatives of people with type 1 diabetes at increased risk of this disease.
A previous trial of oral insulin to prevent Type 1 diabetes hinted that in a group of relatives with insulin antibodies, oral insulin might prevent or delay the disease. Prevention or delay of diabetes would have major clinical ramifications.
Children and adults with normal glucose tolerance who were relatives of patients with type 1 diabetes and had an increased risk for the disease because they had at least two autoantibodies, including insulin autoantibodies.
During a median follow-up of 2.7 years, diabetes was diagnosed in 58 participants (28.5 percent) in the insulin pill group and 62 (33 percent) in the placebo group. Time to diabetes was not significantly different between the two groups.
There are likely many reasons and mechanisms by which type 1 diabetes develops, and the trial assumed that all participants were similar in those characteristics and in their potential response to oral insulin.
Study Conclusions: Among autoantibody-positive relatives of patients with type 1 diabetes, a 7.5 mg insulin pill daily compared with placebo did not delay or prevent the development of type 1 diabetes. These findings do not support oral insulin as used in this study for diabetes prevention.