Modulation of STAT3 Signaling With Siltuximab in Type 1 Diabetes

Inclusion Criteria: 1. Positive for at least one diabetes-related autoantibody any time since diagnosis, including by not limited to: Glutamate decarboxylase (GAD-65) Insulin, if obtained within 10 days of the onset of exogenous insulin therapy; IA-2; ZnT8 2. Peak stimulated C-peptide level ≥ 0.1 pmol/mL following a mixed meal tolerance test (MMTT) conducted within 60 days of enrollment 3. Females of child-bearing potential must be willing to use effective birth control and refrain from donating eggs for the purposes of assisted reproduction for duration of study. 4. A woman of childbearing potential must have a negative serum (β-human chorionic gonadotropin \[β-hCG\]) or urine pregnancy test at screening and prior to dosing. 5. During the study, and for 3 months after receiving the study agent, a woman must agree to not donate eggs (ova, oocytes) for the purposes of assisted reproduction. 6. Willing and able to give informed consent for participation. Exclusion Criteria: 1. History of severe reaction or anaphylaxis to human, humanized or murine monoclonal antibodies; 2. History of malignancy or serious uncontrolled cardiovascular disease or hypertension, nervous system, pulmonary, renal, or gastrointestinal disease, or significant dyslipidemia despite therapy; 3. Any history of recent (within 3 months) serious bacterial, viral, fungal, or other opportunistic infections; 4. History or serologic evidence of current or past HIV, Hepatitis B, or Hepatitis C; 5. Positive QuantiFERON or PPD TB test, history of tuberculosis, or active TB infection; 6. Active infection with EBV ; 7. Active infection with CMV; 8. Diagnosis of liver disease or elevated hepatic enzymes, confirmed by repeat tests, as defined by ALT, AST, or both \> 1.5 x the upper limit of age-determined normal (ULN) or total bilirubin \> ULN; 9. Any of the following hematologic abnormalities, confirmed by repeat tests: * White blood count \<3,000/μL or \>14,000/μL * Lymphocyte count \<500/μL * Platelet count \<150,000 /μL * Hemoglobin \<8.5 g/dL or \> or = to 17 g/dL * Neutrophil count \<2,000 cells/μL 10. Females who are pregnant or lactating; 11. Receipt of live vaccine (e.g. varicella, measles, mumps, rubella, cold-attenuated intranasal influenza vaccine, bacillus Calmette-Guérin, and small pox) in the 6 weeks before treatment; 12. Receipt of non-live vaccine in the 4 weeks before treatment; 13. Any medical or psychological condition that in the opinion of the Sponsor Investigator would interfere with the safe completion of the trial; 14. Receipt of an investigational drug (including investigational vaccines) or used an invasive investigational medical device within 3 months or 5 half-lives before enrollment or is currently enrolled in the treatment stage of an investigational study; 15. Receipt of any immune-modulating biologic drug within 3 months of enrolling in the study.