Herold KC, Bundy BN, Long SA, et al. - A phase 2, randomized, placebo-controlled, double-blind trial of teplizumab (an Fc receptor–nonbinding anti-CD3 monoclonal antibody) including relatives of patients with type 1 diabetes who did not have diabetes but were at high risk for development of clinical disease was carried out by the experts in order to determine the interventions that might impact clinical progression prior to the diagnosis. Expected adverse events of rash and transient lymphopenia were noted. In the teplizumab group vs placebo group, KLRG1+TIGIT+CD8+ T cells were more prevalent. Fewer individuals in the teplizumab group vs the placebo group had diabetes diagnosed among the individuals who were HLA-DR3–negative, HLA-DR4–positive, or anti–zinc transporter 8 antibody–negative. Hence, teplizumab postponed progression to clinical type 1 diabetes in high-risk individuals.