A Multi-step Trial Towards Single Donor Islet Transplantation in Type 1 Diabetic Patients, Using Calcineurin Inhibitor-free Immunosuppression

We designed the clinical trial as a single-arm, phase 1-2 trial conducted in two transplant centers (San Raffaele Scientific Institute, Milan, Italy; Cell Isolation and Transplantation Center, University of Geneva, Geneva, Switzerland) which used a common protocol for islet preparation, post-transplantation patient management and data collection. The trial is exploratory in nature and the target enrollment is 10 patients. The recruitment is competitive between the two centers and each patient is to receive at least 10,000 IE/kg. Up to three islet infusions are allowed per patients until insulin independence is reached, provided that partial islet function (i.e., fasting C-peptide ≥0.3 ng/mL) is maintained between infusions. We planned an individual follow-up of 3 years after the last islet infusion.

Patients with type 1 diabetes are eligible for this study. Major criteria for inclusion are: age 18-65 years; type 1 diabetes with onset <40 years of age; insulin treatment of at least 5 years at the time of enrollment; stimulated C-peptide in response to arginine <0.5 ng/ml; multiple (three or more) daily insulin injections or Continuous Subcutaneous Insulin Infusion; self-blood glucose monitoring ≥3 times/day; high glycemic instability and/or hypoglycemia unawareness; inability to consistently attain a glycated hemoglobin target of <7.5 % without severe hypoglycemia (defined as an hypoglycemic episode requiring the assistance by another person for its resolution) in the past 36 months despite medical management by a diabetes specialist. Major criteria for exclusion are: HbA1c >12%; BMI >30 kg/m2, or insulin requirement > 0.8 IU/kg/day; poorly controlled hypertension; untreated proliferative diabetic retinopathy; presence or history of macroalbuminuria (>300mg/g day) or estimated glomerular filtration rate <60 ml/min/1.73 m2 for females or <70 ml/min/1.73 m2 for males.