The artificial pancreas

It was with great excitement that I received the news on 28 September 2016 that the Food and Drug Administration (FDA) announced the endorsement of the first ‘bionic pancreas’ for marketing in the United States. You might be asking, “What is the significance of this?”, well let me tell you…

The human pancreas naturally supplies a low continuous rate of insulin, known as basal or background insulin. In patients with diabetes, the body’s ability to produce or respond to insulin is impaired.

The bionic pancreas is also called the closed-loop insulin delivery system. This consists of a continuous glucose monitoring (CGM) device with an insulin pump. The Medtronic MiniMed 670G hybrid system is the first of these devices to be approved for patients with Type 1 diabetes older than 14 years.

There is a study currently running to evaluate safety in younger patients – seven to 13 years of age.

This system consists of a sensor attached to the body to measure the blood glucose under the skin, an insulin pump strapped to the body and an infusion patch connected to the pump with a catheter that delivers insulin. The system delivers basal insulin in amounts adjusted according to blood glucose levels detected with the continuous monitor with little to no input of the user. Glucose levels are measured every five minutes. This device increases or decreases or stops insulin as needed according to blood glucose levels.

Currently patients still need to manually request insulin for the carbohydrates they consume. The significance is that stress responses can be monitored better by the automatic response of the basal insulin to blood glucose fluctuations.

In the words of Jeffrey Shuren, the director of Centre for Devices and Radiological Health at FDA, “The FDA is dedicated to making technologies available that can help improve the quality of life for those with chronic diseases, especially those that require day-to-day maintenance and ongoing attention. This first-of-its-kind technology can provide people with Type 1 diabetes greater freedom to live their lives without having to consistently and manually monitor baseline glucose levels and administer insulin.”

During the trial of the closed-loop insulin delivery system, 123 participants with Type 1 diabetes wore the closed-loop system for three months. No serious side effects, diabetic ketoacidosis or severe hypoglycemia were reported. The only side effects noted were skin irritations due to the skin patch.

This is the first of many new technologies coming. The Dexcom G4 and G5 is the first available CGM system available in South Africa that is FDA approved. This CGM device can be used to adjust insulin according to the value of the monitor and you only have to do a finger-stick blood glucose test twice a day as calibration. No more six to eight glucose tests to monitor sugars. This is the start of freedom for people with diabetes; exciting times indeed and the best is yet to come!


Dr Louise Johnson
Dr Louise Johnson is a specialist physician passionate about diabetes and endocrinology. She enjoys helping people with diabetes live a full life with optimal quality. She is based in Pretoria in private practice.