The Effect of Saxagliptin on Glucose Fluctuation and Immune Regulation in Patients With Type 1 Diabetes

Inclusion Criteria: 1. Provision of informed consent prior to any study specific procedures; 2. Diagnosed with type 1 diabetes; 3. Men or women who are 12 to 65 years of age at time of consenting upon Visit 1.; 4. Positivity for at least one of the four islet autoantibodies(IA-2A、IAA、GADA、ZnT8A); 5. 6.5% ≤ HbA1c ≤10.0%. Exclusion Criteria: 1. type 2 diabetes； 2. Evidence of chronic or acute complications of diabetes which is unstable and requires hospitalization； 3. Evidence of disease stress； 4. History of administration of any antihyperglycemic therapy (other than insulin) during the 12 weeks prior to Visit 1； 5. Have a history of, or currently have, acute or chronic pancreatitis； 6. Immunocompromised individuals such as patients that have undergone organ transplantation or patients diagnosed with HIV or patients with agranulocytosis； 7. Evidence of chronic or acute infection； 8. Active liver disease and/or significant abnormal liver function defined as Aspartate transaminase(AST) ≥3x Upper Limit of Normal(ULN) and/or Alanine aminotransferase (ALT) ≥3x Upper Limit of Normal(ULN)； 9. History of unstable or rapidly progressing renal disease, creatinine clearance(CrCl) ≤50ml/min; 10. Congestive heart failure defined as New York Heart Association (NYHA) class III or IV and/or left ventricular ejection fraction of ≤ 40%； 11. Rheumatoid arthritis or other autoimmune disease(except AITD); 12. Hypersensitivity to saxagliptin； 13. History of drug allergy or allergic disease 14. History of alcohol abuse, illegal drug abuse, mental disease or other disease which is not eligible for the study 15. Pregnant or breastfeeding patients； 16. Patients with any diseases which in the judgement of the investigator would compromise the patient's safety or successful participation in the clinical study 17. Any condition where, in the opinion of the investigator, participation in this study may pose a significant risk to the patient or could render the patient unable to successfully complete the study 18. Any disease or condition which the investigator feels would interfere with the trial; 19. Treatment with other immunosuppressive agent such as systemic glucocorticoids other than replacement therapy. Inhaled, local injected and topical use of glucocorticoids is allowed during the last 90 days prior to Visit 1; 20. Participation in a clinical study during the last 90 days prior to Visit 1; 21. Patients who are participating in other clinical study; 22. Treatment with strong cytochrome P450 3A4/5 (CYP3A4/5) inhibitors or other contraindications to therapy as outlined in the saxagliptin package insert; 23. History of haemoglobinopathies (sickle cell anaemia or thalassemias, sideroblastic anaemia).