Diabetes Research Institute Announces First U.S. Patients Off Insulin Using New Method
Miami, FL (October 18, 2001) -- Scientists at the Diabetes Research Institute have successfully transplanted islet cells that have been cultured an average of 34 hours into diabetic patients and achieved insulin-independence in all the patients participating in the clinical trial.
The results were announced Monday at the 10th Anniversary Congress of the Cell Transplant Society, held in Keystone, Colorado.
"This is the first trial in the US to obtain insulin-independence in six of six patients receiving transplanted islet cells that have been cultured prior to infusion and given together with a new regimen of immunosuppressive drugs," explains Camillo Ricordi, M.D., Scientific Director of the Diabetes Research Institute at the University of Miami.
"Widening the window of time during which islets can be transplanted will make it easier for patients to get to the specialized centers where this type of procedure is available, as well as enable transplant teams to better assess the survivability and potency of the cells that are being transplanted. It's a win-win for everyone, and it's an advance that will make islet transplantation more available to all patients who can benefit from it."
Previous trials had suggested that islets, the insulin-producing cells that are destroyed when patients develop type 1 diabetes, had to be transplanted immediately after being isolated from donor pancreases in order to function. This restriction posed many time and logistical limitations for patients and physicians alike. These recent results, however, suggest that clinical islets can be cultured anywhere from several hours to several days, allowing for a more thorough assessment of their viability prior to transplantation. This additional time also allows prospective patients more time for pre-operation immunosuppression regimens to be completed, an important component in this successful strategy.
"Progress in research is always a matter of steps," adds Rodolfo Alejandro, M.D., Director of the DRI's Clinical Islet Transplant Program. "This study, although small, tells us that life without insulin is now a real possibility for many more patients, even for those who yesterday thought they lived too far away from centers like the DRI to entertain the thought."
To participate in this trial patients with Type 1 diabetes needed to have a history of hypoglycemic unawareness, an incapacitating symptom characterized by the inability to detect the early warning signs that usually accompany dangerous drops in blood sugar. It is a patient's ability to recognize these life-threatening signs (dizziness, confusion, tremor, disorientation) and act quickly that help prevent loss of life by allowing the patient to eat something to raise his blood sugar level, pull his or her car over to the shoulder, or otherwise seek assistance quickly.
The study protocol involves isolating the delicate insulin-producing cells from a donor pancreas using a modified version of the Ricordi method, named after its inventor and the DRI's Director. Islets are then cultured for a period ranging from hours to days (range 8-64 hours), during which time they are assessed for potency and viability. In the interim, patients are treated pre-operatively with an induction agent, daclizumab, intended to lower the body's natural immune response and facilitate the transplant's success.
The protocol calls for two infusions of islet cells several days apart, followed by an anti-rejection maintenance regimen consisting of Sirolimus/Tacrolimus, drugs previously used for anti-rejection of transplanted tissues. All six patients in the study no longer required insulin after completing the second islet infusion, achieved metabolic control with blood sugar levels well within the normal range, and did not experience episodes of hypoglycemic unawareness. The study's first patients are currently in post-operative day 145, with more patients listed and awaiting their turn.
Mitra Zehtab, MD, MBA