Type 1 diabetes is commonly treated with the administration of insulin, either by multiple insulin injections or by a continuous supply of insulin through a wearable pump. Insulin therapy allows long-term survival in individuals with type 1 diabetes; however, it does not guarantee constant normal blood sugar control. Because of this, long-term type 1 diabetic survivors often develop vascular complications, such as diabetic retinopathy, an eye disease that can cause poor vision and blindness, and diabetic nephropathy, a kidney disease that can lead to kidney failure. Some individuals with type 1 diabetes develop hypoglycemia unawareness, a life-threatening condition that is not easily treatable with medication and is characterized by reduced or absent warning signals for hypoglycemia. For such individuals, transplantation of pancreatic islets is a possible treatment option. Unfortunately, insulin independence among islet transplant recipients tends to decline over time. New strategies aimed at promoting engraftment of transplanted islets are needed to improve the clinical outcomes associated with this procedure. The purpose of this study is determine the safety and efficacy of islet transplantation, when combined with an immunosuppressive medication regimen containing belatacept, for treating type 1 diabetes in individuals experiencing hypoglycemia unawareness and severe hypoglycemic episodes. This study will also seek to improve the understanding of determinants of success and failure of islet transplants for type 1 diabetes.~Eligible participants will be randomly assigned to this study or a site-specific Phase 3 islet transplantation study (CIT-07). Participants in this study will receive up to three separate islet transplants and a regimen of immunosuppressive medications consisting of belatacept, basiliximab (an IL-2 monoclonal antibody receptor blocker), and mycophenolate mofetil. Participants will begin receiving all three drugs on the day of the first islet transplant. Belatacept will also be administered again on Days 4, 14, 28, 56, and 84 post-transplant and then every 4 weeks for the duration of the study.~If the participant receives daclizumab, it will also be given again on Days 14, 28, 42, and 56 post-transplant; if the participant receives basiliximab, it will also be given again on Day 4 post-transplant. Mycophenolate mofetil will also be given for the duration of the study.~Transplantations will involve an inpatient hospital stay and intraportal infusion of islet cells. Participants who do not achieve or maintain insulin independence by Day 75 post-transplant will be considered for a second islet transplant. Participants who remain dependent on insulin for longer than 1 month after the second transplant and who show partial graft function will be considered for a third islet transplant. Participants who do not meet the criteria for a subsequent transplant and do not have a functioning graft will enter a reduced follow-up period.~There will be up to 25 study visits following each transplant. A physical exam, review of adverse events, and blood collection will occur at most visits. A chest x-ray, abdominal ultrasound, electrocardiogram, quality of life questionnaires, urine collection, and more extensive blood testing will occur at some visits. Participants will also test their own blood glucose levels at least five times per day throughout the study. A 24-month follow-up period will take place after the participant's last transplant.
Type 1 diabetes is an autoimmune disease in which the insulin-producing pancreatic beta cells are destroyed, resulting in poor blood sugar control. The purpose of this study is to determine the safety and effectiveness of islet transplantation using a steroid-free, calcineurin-inhibitor-free belatacept based immunosuppressive medication, for treating type 1 diabetes in individuals experiencing hypoglycemia unawareness and severe hypoglycemic episodes.