A multicentre clinical trial has found a new closed-loop system
that uses advanced control algorithms to automatically monitor and
regulate blood glucose levels was more effective than existing
treatments at controlling blood glucose levels in people with type 1
The study from the Ichan School of Medicine, published in the
New England Journal of Medicine, showed that the closed-loop
system improved participants' blood glucose control throughout
the day and overnight.
Overnight glucose control is a common but serious challenge for
children and adults with type 1 diabetes, since blood glucose can
drop to dangerously low levels when a person is asleep.
The closed-loop system also known as the artificial pancreas, is
an "all-in-one" diabetes management system that tracks blood
glucose levels using a continuous glucose monitor (CGM) and
automatically delivers insulin when needed, using an insulin
The system replaces reliance on testing by finger prick or CGM
with separate delivery of insulin by multiple daily injections or a
The international multicentre study involves five separate
artificial pancreas clinical protocols implemented by 10 research
centres which included the Icahn School of Medicine at Mount
This six-month study was the third phase in the series of
trials. It was conducted with participants living their usual
day-to-day lives, so the researchers could best understand how the
system works in typical daily routines.
The study involved 168 participants aged 14 or older with type 1
They were randomly assigned to use either the closed-loop system
from Tandem called Control-IQ or sensor-augmented pump (SAP)
therapy with a CGM and insulin pump that did not automatically
adjust insulin throughout the day.
Participants had contact with study staff every two to four
weeks to download and review device data. No remote monitoring of
the systems was done, so that the study would reflect real-world
The researchers found that users of the artificial pancreas
system significantly increased the amount of time in which their
blood glucose levels remained within the target range of 3.9 -
10 mmol by an average of 2.6 hours per day, while the time in
range in the SAP group remained unchanged over six months.
Closed-loop users also showed improvements in time spent with
high and low blood glucose, haemoglobin A1c, and other measurements
related to diabetes control compared to the SAP group.
The Control-IQ technology was derived from a system originally
developed at the University of Virginia, Charlottesville.
In this system, the insulin pump is programmed with advanced
control algorithms based on a mathematical model that uses the
person's glucose monitoring information to automatically adjust the
Dr Carol Levy, lead researcher on the trial said, "This system
has some unique features to help patients achieve target glucose
levels while reducing the risk of hypoglycaemia. It has been an
exciting study both for patients and the research team. By making
management of type 1 diabetes easier and more precise by using
closed-loop technology, the potential is tremendous to reduce the
daily burden of this [condition] and improve long-term outcomes for