Rezpegaldesleukin (NKTR-358) in New Onset Type 1 Diabetes Mellitus

This protocol will enroll 66 participants within 100 days of T1D diagnosis who will be treated with either rezpegaldesleukin or placebo with subcutaneous injections over 26 weeks, administered once every 14 days. The rezpegaldesleukin/placebo treatment will be administered at the study site. Mixed meal tolerance testing will be done at the screening, baseline visit (V0) and at 3, 6 and 12 months during the study. Once the 26-week treatment period has been completed, participants will continue follow-up visits until 12 months from the baseline visit.