The US Food and Drug Administration issued a software recall after a defective diabetes management iPhone app reportedly shut off insulin pumps, injuring at least 224 users. Initially approved by the FDA in February 2022, Tandem Medical Care’s t:connect iOS app was the first of its kind to receive regulatory approval. Once downloaded, t:connect works alongside Tandem’s t:slim X2 insulin pump by allowing diabetes patients to issue bolus doses of insulin over Bluetooth.

Shortly following the app’s 2.7 update in March 2023, however, users began to report premature device shutdowns. Further investigation determined a software bug caused the app to repeatedly crash and relaunch, subsequently draining the actual insulin pump’s battery through Bluetooth communication strains. The t:slim X2 has always notified users of impending shutdowns through low-power alerts and alarms, but at least 224 people still reported complications due to the unexpected pump failures.

On March 27, Tandem issued an “Urgent Medical Device Correction” notice to its customers warning of the defect and explained the problem “could lead to an under-delivery of insulin and may result in hyperglycemia, including severe hyperglycemia.” Severe hyperglycemia can induce diabetic ketoacidosis requiring hospitalization and emergency medical services. The software patch was also announced at the same time.

The FDA announced the new Class I recall, its “most serious” type, on Wednesday for version 2.7 of the t:connect iOS app. They also warned that continued use “may cause serious injuries or death,” although no deaths have so far been reported due to the issue. Tandem has already contacted customers and released an over-the-air 2.7.1 patch that “should fix the defective software.”

To determine their current t:connect version, owners are directed to open the app, click the “Setting” icon, then click “About.” If necessary, accessing t:connect on the iOS App Store will allow users to manually update the app.

While the new update appears to solve the issue, the FDA and Tandem warn t:slim and t:connect owners to read all system alerts and their phone’s app notifications, as well as make sure their smartphones and medical devices are fully charged before going to sleep at night.

“Giving a meal bolus is now the most common reason a person interacts with their pump, and the ability to do so using a smartphone app offers a convenient and discrete solution,” Tandem Diabetes Care CEO and President John Sheridan said in a statement at the time of t:connect’s initial release.

In its App Store “Version History,” Tandem wrote the 2.7.1 patch was for “Overall app performance updates.”

Tandem Diabetes Care has provided the following statement:
“Before the FDA recall notice, Tandem implemented a fix for the issue and more than 98% of impacted customers have already updated their devices. Any customers who need assistance with a software update can reach Tandem’s Customer Technical Support team 24/7 at 877-801-6901.”