This study will evaluate the safety, tolerability and efficacy of transplantation of experimental islet cells as a potential treatment for brittle type 1 diabetes mellitus. It will also assess the safety, tolerability and efficacy of AT-1501 in an immunomodulation regimen in adult patients with brittle T1D undergoing an islet cell transplant. This is a single arm open-label study and up to 6 participants will be recruited at a single center in the United States.
The objectives include:
* To assess the safety and tolerability of transplanted islet cells and immunomodulation with AT-1501, in combination (AT+) with rabbit anti-thymoglobulin (ATG), etanercept and mycophenolate mofetil (MMF/EC-MPS) in adults with T1D undergoing islet cell transplant.
* To assess the efficacy of transplanted islet cells and immunomodulation with AT-1501 in adults with brittle T1D undergoing islet cell transplant.
The duration of treatment may vary from participant to participant and could be up to 2 years. Participants may receive up to 2 islet cell transplants.
