Treatment 4 min read

Personalized Insulin Pumps Help Patients With Type 1 Diabetes

New closed-loop systems being tested in clinical trials act like artificial pancreas, monitoring and ensuring healthy blood sugar levels.

By Audrey Carson featured image Iuliia Safronova/Getty Images

Managing type 1 diabetes is a full-time job, one that bears an unrelenting reminder of the chronic disease through daily injections and pinpricks. But a new clinical trial for a personalized intervention could pave the way to easing the burden for patients with diabetes.

Sponsored by Medtronic, the multicenter nationwide trial is testing a first-of-its-kind, FDA-approved system that uses artificial intelligence to monitor and control participants’ blood glucose levels. Medtronic first released the MiniMed 670G device used in the trial in 2016 after the FDA decided to fast-track the system’s approval.

Now, investigators are enrolling patients for the second cohort of Medtronic’s four-year clinical trial with the aim of having 1,000 subjects complete the study. The trial divides subjects into three cohorts: those currently using insulin pumps but not blood glucose sensors; those using a pump and a sensor; and those using neither pumps nor sensors.

Linda Aman, a sub-investigator on the trial, has patients who drive several hours to participate at the Grunberger Diabetes Institute, one of the trial sites in Bloomfield Hills, Michigan, for the promise of a more automated insulin delivery system.

“Basically what this pump does, it is supposed to reduce the burden of taking care of [type 1] diabetes,” Aman says. “It’s a very high burden. You have to deliver your insulin somehow either with a pump or with injections or you can inhale it. But you have to do all this in contest with what your blood sugars are doing, so you need to test those frequently. Some people test as much as 10 times a day. There are people who are just more adept at doing that than others.”

The MiniMed 670G system includes both an insulin pump and a continuous glucose monitor that work in tandem to keep blood glucose levels in a normal range. The monitor includes a sensor that is placed under the abdominal skin and measures glucose levels in the tissue fluid every five minutes. The monitor wirelessly transmits these readings to the pump where patients can view a display screen indicating if levels are out of range. Users can then deliver the appropriate insulin dose.

The pump can operate in either manual mode where the user sets a preprogrammed basal insulin delivery rate or auto mode where the pump automatically adjusts insulin levels based on sensor readings. In auto mode, the pump updates every 24 hours to better accommodate an individual’s daily blood glucose patterns. The longer a user wears the pump in auto mode, the “smarter” it becomes.

Aman says their participants have seen A1C levels, a three-month measure of blood glucose, drop by as much as two percent since May 2017, when the trial began. Because of this unexpected drop, she says they are now enrolling patients with higher A1C levels to see if the use of the system will continue to drop A1C levels so that they are in a healthy range.

“If just changing equipment is going to lower blood sugar levels, this is phenomenal,” Aman says. “This is good stuff.”

Type 1 diabetes is a chronic disease that results in high blood glucose levels. Normally, insulin — a hormone produced by beta cells in the pancreas — transports glucose from the blood into cells, Aman says. But individuals with type 1 diabetes have damaged beta cells that produce little to no insulin. To compensate, they use either multiple daily insulin injections or an insulin pump that delivers a constant dose of insulin in the background and higher doses based on meals. They also need to constantly monitor blood glucose levels, which are easily affected by the ups and downs of everyday life.

“Any changes like stress, increased activity, exercise can affect that balance where they can experience either higher glucoses or hypoglycemia, low glucoses,” says Elizabeth Buschur, an endocrinologist at The Ohio State University Wexner Medical Center. “And that can be both disrupting to their everyday life as well as dangerous at times if it’s not recognized in the early signs.”

Buschur notes that while pumps and sensors have been on the market for some time, more medical companies are pursuing technology similar to that of new Medtronic system that integrates a pump and sensor communication system. Last September, the FDA also approved a fast-acting insulin to be used with meals to more quickly absorb blood glucose. Other advancements in treatment, moving toward an eventual cure, include research into beta cell transplants and stem cell therapy, Buschur says.

“People have been looking at curing the disease for years now, and I think that that will happen at some point in the future. It’s really difficult to say when that might be,” Buschur says. “But there are advancements in looking at different immune-modulating agents to be able to do that.”