CNP-103 in Adolescent and Adult Subjects Ages 12-35 With Recently Diagnosed (Within 6 Months) Stage 3 Type 1 Diabetes (T1D)

Inclusion Criteria: 1. Participants who are willing and able to provide Institutional Review Board (IRB) approved written informed consent and privacy language as per national regulations. 2. Men and non-pregnant, non-breast-feeding women ages 12-35 years inclusive. 3. Documented diagnosis of T1D within 180 days prior to study enrollment according to at least 1 of the American Diabetes Association \[ADA\] criteria. 4. Participants must be on standard of care diabetes management (e.g., insulin therapy, a nutrition plan, regular exercise, or other relevant specialty care). 5. Participants with a peak stimulated C-peptide of \>0.2 nmol/L measured from a mixed meal tolerance test (MMTT). Note: this test result may be obtained from an MMTT conducted within 1 month of planned first dose. 6. Participants with an episode of diabetic ketoacidosis (DKA) must have a MMTT performed no sooner than 2 weeks and up to 4 weeks after resolution of the DKA event to have a qualifying C-peptide reading. 7. Participants on systemic corticosteroids or any medication used to treat the symptoms of T1D must undergo a washout period of at least two weeks prior to enrollment and must agree to use a non-steroid alternative throughout the trial, if necessary, for any disorder requiring corticosteroids. In addition, participants must be on a stable dose of any other medications, other than insulin, for a minimum of 1 month prior to enrollment and must agree not to increase their dose from the Screening Visit through the End of Study Visit unless reviewed and approved by the medical monitor and the principal investigator. Exclusion Criteria: 1. Participants who have used the following medications: a. Within 5 half-lives or 90 days prior to first dose, whichever is shorter: * Oral immunomodulators (e.g., cyclosporin, azathioprine, methotrexate) * B cell depleting immunotherapy (e.g., Rituximab) 2. Other anti-diabetic agents besides insulin (e.g., Verapamil). 3. Within 6 months prior to first dose: a. T cell modifying immunotherapy (e.g., Abatacept, Etanercept, Ustekinumab) 4. Within 12 months prior to first dose: a. T cell depleting immunotherapy (e.g., Teplizumab) 5. Exclusion of additional immunomodulation will be at the discretion of the medical monitor and study site Investigator.