The US Food and Drug Administration (FDA) has approved the first interoperable insulin dosing "controller" software that connects enabled insulin pumps and continuous glucose monitors, adding a new step toward fully automated insulin delivery.

The Tandem Diabetes Care Control-IQ Technology connects to an "alternate controller-enabled" insulin pump, aka "ACE pump," and an "integrated continuous glucose monitor," or "iCGM."

"This is the first such controller that can be used with other diabetes devices that are also designed to be integrated into a customizable diabetes management system for automated insulin delivery," according to an FDA statement.

The agency noted that the authorization "paves the way for iCGMs and ACE pumps to be used with an interoperable automated glycemic controller as a complete automated insulin dosing (AID) system."

The FDA approved the t:Slim X2 as the first ACE pump in February 2019 and the Dexcom G6 as the first iCGM in March 2018.

"This is fantastic news that the diabetes community has been eagerly awaiting," diabetes technology expert David T. Ahn, MD, program director of the Mary and Dick Allen Diabetes Center at Hoag Hospital, Newport Beach, California, told Medscape Medical News. "By pairing with the Dexcom G6, the Control IQ technology is the first to offer automated insulin titration without fingersticks."

The approval was based in part on data from the International Closed Loop trial of 168 patients with type 1 diabetes. Published in the New England Journal of Medicine in October 2019, the study showed that the Tandem t:slim X2 insulin pump and the Dexcom G6 CGM with the Control-IQ technology resulted in approximately 2.6 more hours per day spent with blood glucose levels in the target range of 70 to 180 mg/dL compared with the two separate noncommunicating devices, with 13 fewer minutes per day spent with glucose levels below 70 mg/dL.

The technology adds a new step in the progression toward fully "closed-loop" or "artificial pancreas" development. In addition to currently available controller software capabilities that automatically adjust basal insulin infusions to prevent high and low blood glucose levels (ie, the Medtronic 670G), the Control-IQ technology also can deliver bolus doses when glucose levels are predicted to exceed a predefined threshold.

According to Ahn, who has no financial relationships with Tandem or Dexcom, "it is the first hybrid closed-loop algorithm to offer automated correction boluses, which led to an impressive 100% retention of study patients in their pivotal clinical trial."

And, he added, "Also unique to the Tandem, similar to an iPhone software update introducing new features, the Control IQ feature will be available via a free downloadable software update that can be applied to any Tandem X2 pump, which has been the market for a couple years."

The FDA statement cautioned that although the system has been assessed for reliability, "incorrect and inappropriate calculation, and command, delay of insulin delivery can still occur.

"Other risks associated with use of the interoperable controller can include incorrect insulin delivery as a result of loss of communication between connected devices, or from exploitation of cybersecurity vulnerabilities," potentially leading to hypoglycemia or hyperglycemia, the FDA notes.

Nonetheless, Ahn said, "the approval as an ACE pump with compatibility with iCGM is the formal introduction to a world of automated insulin delivery where users can choose their preferred insulin pump and continuous glucose monitoring system. Patients win with more options to choose from."