Timing of Immunotherapy in Type 1 Diabetes: The Earlier, the Better?

In 1986, The New England Journal of Medicine published George Eisenbarth's (Eisenbarth. 1986. N. Engl. J. Med. 314: 1360-1368) model of type 1 diabetes (T1D) as a chronic autoimmune disease. In 2019, the same journal published the results of the teplizumab trial, which showed the anti-CD3 mAb delayed T1D progression in high-risk individuals. Although teplizumab is the first immunomodulatory agent to demonstrate significant delay in disease progression, it is also one of the few tested prior to clinical disease onset. Is it possible, then, that this trial's success is as much about the agent as it is about its timing? This commentary will review the landscape of immune intervention in T1D since 1986, discuss the teplizumab trial results, and finally, speculate on whether current paradigms for T1D immune intervention should focus less on disease development as a continuum and more on the stages of T1D progression as distinct disease processes.