168-OR: Five-Year Follow-up after Islet Transplantation in Nonuremic Patients with Type 1 Diabetes Mellitus and Hypoglycemia Unawareness: Favorable Long-Term Outcomes of Multicenter Trial at University of Chicago

Introduction: Prospective randomized multicenter trial did not find advantage of CXCR1/2 blocker (Reparixin) over placebo in islet transplantation in patients with type 1 diabetes mellitus and problematic hypoglycemia at 1 year follow-up. We note favorable metabolic outcomes at 5-year follow-up in trial cohort from our center.

Material and Methods: 12 patients with type 1 diabetes and problematic hypoglycemia received a total 19 islet transplants (max 2 per patient) within one year. Eight patients were randomly assigned and received Reparixin and 4 received placebo within first week after each transplant in addition to standard immunosuppression (anti-thymocyte globulin, tacrolimus, and mycophenolate).

Results: 11/12 patients achieved insulin independence during the study period. At 5-year follow-up 4/8 (50%) remained insulin free with HbA1c <6.0 % in Reparixin group vs. 1/4 (25%) in placebo group. One patient had partial islet function without severe hypoglycemic episodes (SHE). Diabetic neuropathy and renal function remained unchanged while retinopathy improved in 3/6 (50%) patients. 6/12 (50%) patients left the study: 3/6 proceeded with pancreas transplant and remain off insulin, the remaining 3/6 stopped immunosuppression with decline of islet graft function, deterioration of glucose control (HbA1c > 7.0 %), and recurrence of SHE. No patients experienced any cardiovascular events nor became persistently sensitized (current PRA 0%).

Conclusions: Repeat islet transplantation led to insulin independence in 91% of patients; 50% of patients in Reparixin group and 25% in placebo. Secondary diabetic complications did not progress. No patients became persistently sensitized. Subsequent pancreas transplantation was feasible and effective in patients with decline of islet graft function.