Tandem Diabetes Care issues voluntary device correction for certain insulin pumps

Aug 7 (Reuters) - Tandem Diabetes Care TNDM.O issued a voluntary correction for an insulin pump model due to a speaker malfunction that disrupts communication with glucose monitoring systems, potentially causing high blood sugar levels.

Shares of the company fell more than 27% in premarket trading, following issues with the t:slim X2 insulin pumps.

The firm reported 700 adverse events and 59 injuries associated with the defect, "Malfunction 16", but no deaths. However, in severe cases, users may require hospitalization or medical intervention, Tandem added.

As part of the correction, Tandem sent notices to impacted U.S. customers between July 22 and 24, 2025, with instructions on what to do in the event of a malfunction.

It will also release a software update to enhance early detection of speaker failures and introduce vibration alerts to help reduce potential safety risks.