Tandem Diabetes Care releases updated iOS t:connect mobile app for users of t:slim X2 insulin pumps affected by nationwide recall in March 2024 Page 1

Tandem Diabetes Care, Inc. (Nasdaq: TNDM) today announced the planned release of version 2.8.2 of its Apple iOS t:connect mobile app in the United States on August 20, 2024, to address an issue described in a March 2024 recall that could result in rapid battery drain on a user’s t:slim X2 insulin pump. This battery drain could cause the pump to fail sooner than expected, which some customers are still seeing following the release of version 2.7.1 of the app in March. Tandem encourages all affected t:slim X2 iOS users to update their mobile app once the new version is available in the Apple App Store.

Too little insulin due to a pump malfunction can lead to hyperglycemia or diabetic ketoacidosis, which can be a life-threatening condition due to high blood sugar and a lack of insulin. There are 143 confirmed adverse events associated with this recall. Adverse events are defined as a confirmed high blood sugar and/or an event requiring medical attention. There have been two hospitalizations and no deaths reported.