Immunotherapy delays type 1 diabetes mellitus in high-risk individuals

Certain individuals at high risk of developing type 1 diabetes mellitis (T1DM) can delay progression to clinical disease by two years or more with a two-week course of teplizumab, according to the results of a phase II study published in The New England Journal of Medicine (9 June 2019)^[1].

Teplizumab, an anti-CD3 monoclonal antibody, modifies CD8+ T cells, which are thought to play a role in the destruction of insulin-producing beta cells.

Researchers enrolled 76 participants aged 8–49 years who were relatives of people with T1DM, had at least two types of diabetes-related autoantibodies and abnormal glucose tolerance.

The participants were randomly assigned to a 14-day course of teplizumab or placebo, with oral glucose tolerance tests performed every six months or until participants developed T1DM.

Of the 32 participants allocated to placebo, 23 (72%) developed diabetes, compared with 19 (43%) of the 44 participants allocated to the teplizumab group. The median time for people in the control group to develop diabetes was 24.4 months, compared with 48.4 months for those who received teplizumab.

The researchers, who were led by Kevan Herold, professor of immunobiology and medicine at Yale University, said: “The delay of progression to diabetes is of clinical importance, particularly for children, in whom the diagnosis is associated with adverse outcomes.”