Efficacy and Safety of Teplizumab in Japanese Participants With Stage 2 Type 1 Diabetes

This is a parallel, Phase 2, two-arm study to assess the efficacy and safety of 14-days intravenous (IV) infusion of teplizumab treatment. Teplizumab has been approved by FDA to delay the onset of Stage 3 Type 1 Diabetes (T1D) in adults and pediatric patients aged 8 years and older with Stage 2 T1D. The dose regimen of teplizumab in this study is consistent with the regimen approved by US FDA. Given prior clinical studies conducted in Western countries, this design is appropriate to assess the efficacy, safety and tolerability, pharmacokinetic, pharmacodynamic, and immunogenicity of a 14-day IV infusion regimen of teplizumab in Japanese Stage 2 T1D participants aged 1 to 34 years.

Inclusion Criteria: * Male or female Japanese participant, 1 (inclusive) to 34 years (inclusive) of age, at the time of signing the informed consent. Japanese: born in Japan or ethnic Japanese born outside of Japan, and a descendent of 4 ethnic Japanese grandparents who were all born in Japan. * Confirmed diagnosis of Stage 2 T1D based on following criteria: * Participant is positive for 2 or more T1D related auto-antibodies (confirmed by written medical history and/or obtained at study screening). The autoantibodies that are to be confirmed are anti-GAD (glutamic acid decarboxylase), anti-IA2 (insulinoma-associated antigen 2), anti-insulin, anti-ZnT8 (zinc transporter 8), and/or ICA (islet cell antibody). * Oral glucose tolerance test (OGTT) or blood HbA1c confirms the participant has dysglycemia without overt hyperglycemia. * Participant must be in good health (except for being Stage 2 T1D) as determined by medical e)valuation including medical history, physical examination, laboratory tests, and electrocardiogram (ECG) XE " ECG " \\f Abbreviation \\t "electrocardiogram" . * Participant is up to date with routine age-appropriate immunizations according to current local specific guideline prior to randomization. * Female participants should use contraceptives consistent with local regulations regarding the methods of contraception for those participating in clinical studies. * A female participant is considered fertile (woman of childbearing potential - WOCBP) from the time of menarche until becoming postmenopausal unless permanently sterile. Female participants are eligible to participate if one of the following conditions applies: * Is a woman of nonchildbearing potential (WONCBP) OR * Is a WOCBP and agrees to keep abstinent from heterosexual intercourse as their preferred and usual lifestyle (abstinent on a long term and persistent basis) and agree to remain abstinent, or use other highly effective contraceptive method, from signing of the informed consent to at least 3 months and 2 weeks after randomization and agrees not to donate or cryopreserve eggs (ova, oocytes) for the purpose of reproduction during this period. A WOCBP must have at least a negative highly sensitive pregnancy test within 48 hours before the administration of study intervention. If a urine test cannot be confirmed as negative (eg, an ambiguous result), a blood pregnancy test is required. In such cases, the participant must be excluded from participation if the serum pregnancy result is positive. Participants are excluded from the study if any of the following criteria apply: * Any presence of clinically relevant cardiovascular, pulmonary, gastrointestinal, dermatologic, hepatic, renal, metabolic (except Stage 2 T1D), hematological, neurological, osteomuscular, articular, psychiatric, systemic, ocular, gynecologic (if female), or infectious disease, or signs of acute illness. * Participant has clinical signs and symptoms consistent with COVID19, eg, fever, dry cough, dyspnea, loss of taste and smell, sore throat, fatigue or confirmed infection by appropriate laboratory test within the last 4 weeks prior to Screening. Participant who had severe course of COVID-19 (ie, hospitalization, extracorporeal membrane oxygenation, mechanically ventilated). * For participant ≥18 years, blood donation of 400 mL within 12 weeks (male) or 16 weeks (female), 200 mL within 4 weeks or apheresis donation within 2 weeks before randomization; for participant \