Low Dose Antithymocyte Globulin (ATG) to Delay or Prevent Progression to Stage 3 T1D (TN28 Protocol)

This phase 2 trial is a double-blind, randomized, placebo-controlled clinical trial in male and female adolescent and adult participants (ages 12-35 years) with newly diagnosed Stage 3 T1D (within 100 days of diagnosis). Enrollment into abrocitinib and ritlecitinib arms and the shared placebo arm will occur in a 1:1:1 allocation with a planned enrollment of 26 participants in each arm. Participants will receive 12 months of active treatment with abrocitinib, ritlecitinib, or placebo with up to 12 months of additional follow-up. A total sample size of 52 participants will receive active treatment, and a total of 26 participants will receive placebo.