The US Food and Drug Administration (FDA) has tagged Abbott’s recent recall of its faulty FreeStyle Libre 3 sensors as Class I, the most serious designation the agency can hand out for a recall.

The FreeStyle Libre 3 sensor is a component of Abbott’s popular FreeStyle Libre 3 continuous glucose monitoring system (CGM).

Abott’s FreeStyle Libre range generated $1.4bn in sales in Q4 2023, representing sales growth of 25.5%.

CGM is a category of diabetes medical devices that use a sensor under the skin to measure glucose levels in real time, with information then transmitted to a linked handset or smartphone. Systems such as the FreeStyle Libre 3 help people manage diabetes by providing information on glucose levels so treatment can be adjusted if needed.

The issue with Abbott’s technology relates to a small number of sensors in the US providing incorrect high glucose readings. This, the FDA states, could pose a potential health risk for people living with diabetes.

Patients who see a high reading may, in fact, have severe low blood sugar – hypoglycaemia – leading to severe health problems such as loss of consciousness, seizures, and brain damage, among others. The FDA stated two injuries have been reported due to the faulty sensors, with no reported deaths.

Abbott recalled the devices in July, issuing a notice to all affected customers to immediately discontinue use and dispose of faulty sensors. Lot numbers affected are T60001948, T60001966 and T60001969 distributed in the US, as per the FDA notice. The FreeStyle Libre 3 reader and app are not affected.

In a statement to Medical Device Network, an Abbott spokesperson said “Internal testing determined that some of these sensors may provide incorrect high glucose readings, which, if undetected, may pose a potential health risk for people living with diabetes. We’ve been instructing consumers to visit www.FreeStyleConfirm.com to see if their sensors are affected and to get a replacement product”.