An AE was any untoward medical occurrence in a participant or clinical study participant,temporally associated with use of study dose,whether or not considered related to study dose.AESI was any AE that met any of following:All \>=Grade 3 infections (including all opportunistic infections);acute mononucleosis-like illness;lymphomas or other malignancies;severe hypoglycemic episode;\>=Grade 3 liver function abnormalities, thrombocytopenia, neutropenia or rash;\>= Grade 4 allergic/hypersensitivity reaction (anaphylaxis) or cytokine-release syndrome; lymphocyte count \<500/cubic millimeter for 7 days or longer. An SAE was as any untoward medical occurrence that,at any dose:resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization,resulted in persistent disability/incapacity, was a congenital anomaly/birth defect or any other medically important event.A TEAE was any AE which started during or after the first dose of teplizumab.