Type 1 Diabetes (T1D) Clinical Trials

• Participants are eligible to be included in the study only if all of the following criteria apply:

• Participant must be 1 to 25 years of age inclusive, at the time of signing the informed consent.

• Participants diagnosed with T1D Stage 3 according to American Diabetes Association 2025 criteria

• Participants able to be randomized and initiate study drug within 8 weeks (56 days) of the Stage 3 T1D diagnosis

• Participants must be positive for at least one T1D autoantibody at screening:

• Glutamic acid decarboxylase (GAD-65),

• Insulinoma Antigen-2 (IA-2),

• Zinc-transporter 8 (ZnT8), or

• Insulin (if obtained not later than 14 days after exogenous insulin therapy initiation).

• Islet cell cytoplasmic autoantibodies (ICAs)

• Have random C-peptide level ≥0.2 nmol/L obtained at screening

• Enter Inclusion Criteria Sex

• Both male and female participants are eligible.

• Contraceptive use by women should be consistent with local regulations regarding the methods of contraception for those participating in clinical studies.

• A female participant is eligible to participate if she is not pregnant, and one of the following conditions applies:

• Is a woman of nonchildbearing potential (WONCBP) OR

• Is a woman of childbearing potential (WOCBP) and agrees to use a contraceptive method that is highly effective, with a failure rate of \<1% during the study intervention period (to be effective before starting the intervention) and for at least 30 days after the last administration of study intervention.

• A WOCBP must have a negative highly sensitive pregnancy test at screening (serum) and within 24 hours (urine or serum as required by local regulations) before the first administration of study intervention.

• Lactating woman must interrupt breastfeeding and pump and discard breast milk during and for 20 days after last administration of study intervention.

• Capable of giving signed informed consent as described in Appendix 1 of the protocol which includes compliance with the requirements and restrictions listed in the informed consent form (ICF) and in the protocol.

⁃ Note: For minor participants, a specific ICF must also be signed by the participant's legally authorized representative (LAR).