In September 2016, the first closed loop insulin delivery system, also known as the “artificial pancreas”, was approved by the FDA for use in patients with type 1 diabetes. Medtronic’s Minimed 670G is a two device insulin delivery and glucose monitoring system that continuously delivers insulin and checks blood sugars every 5 minutes. Through an algorithm and real time data, the pump can adjust rates of basal insulin delivery to keep blood sugars within the target range. Patients will still need to input carbohydrate information for bolus insulin delivery to cover the food they eat. FDA approval came after a study, funded by the Juvenile Diabetes Research Foundation, assessed the impact of the closed loop system on Hemogloblin A1C and glucose variability over a 3 month time period. The study reported a decreasee in A1C from a mean of 7.4 (SD 0.9)% to 6.9 (SD 0.6)% with the percent of glucose values within target range increasing from 66.7% to 72.2% during that time. The number of hypoglycemic and hyperglycemic events experienced during the day and overnight improved over the time period as well (JAMA 316(13):1407-1408).

Type 1 diabetes is a chronic disease that affects over 1.25 million adults and children within the United States alone. Management of this lifelong illness includes frequent blood sugar checks and insulin administration, monitoring of food intake and adjustment of insulin doses for illness, menses, stress and activity. The risk of long-term microvascular and macrovascular complications, such as nephropathy, retinopathy, neuropathy and cardiovascular disease, increases with poor glycemic control. In the past, fixed injections of insulin with fixed meal times and carbohydrate quantities served as the treatment plan. Over the years this was replaced by multiple daily injections of insulin to allow for more freedom with respect to eating behaviors, followed by insulin pump therapy, which delivers insulin through a cannula that is inserted under the skin. The addition of the continuous glucose monitor has allowed us to assess the minute to minute variations in blood sugar, which has led to improvements in glycemic control as well as quality of life for patients and their caregivers.

The Minimed 670G is approved for use in adults and children 14 years of age and older. Studies are currently underway assessing the safety and efficacy of its use in children with type 1 diabetes between the ages of 7 and 13 years. The 670G is due to be available to patients in the spring of 2017.

– Rushika Conroy, MD