The HCL system is designed to automatically control blood glucose levels with minimal input or supervision from patients or caregivers. The system, using Medtronic’s MiniMed 670G insulin pump, 4th-generation sensors and a control algorithm, was used in a 3-month study of 124 patients with Type I diabetes; 99 subjects opted for a continued-access program after the initial trial ended.
The HCL system logged a glucose reading every 5 minutes during the trial, but patients still had to occasionally calibrate the sensors and take mealtime or corrective insulin doses.
After some 12,400 patient-days, the study showed, there were no incidents of diabetic ketoacidosis, severe hypoglycemia or serious device-related adverse events. Patients showed lower percentages of low blood sugar at night while using the HCL system, and mean HBA1c levels fell.
“The HCL system was safe, acceptable, and associated with improved glucose control during extended at-home use,” the study’s authors wrote.
“We are proud to be the first company to present results of a pivotal trial of a closed loop system, which is designed to automatically control glucose levels 24 hours a day with less input from patients, as we continue toward our goal of helping people with diabetes enjoy greater freedom and better health,” Dr. Francine Kaufman, Medtronic Diabetes chief medical officer, said in prepared remarks.
“The ability for people with diabetes to achieve better glucose control and live longer, healthier lives has significantly improved with insulin pumps and continuous glucose monitoring systems. However, patients must still make frequent decisions each day while using today’s systems,” added lead author Dr. Richard Bergenstal of the International Diabetes Center in Minneapolis. “Simplifying this self-management and adding a little peace of mind with this more automated Hybrid Closed Loop system would impact these patients’ lives in a very meaningful way.”
Medtronic has said that it expects to file this month for FDA approval for the MiniMed 670G.