FDA Issues Warning Letter to Abbott Over FreeStyle Libre CGM Accuracy

Abbott has received a warning letter from the US Food and Drug Administration (FDA) citing accuracy-related issues with its FreeStyle Libre continuous glucose monitors (CGMs). Dated 23 January and posted this week, the letter focuses on deficiencies in performance specifications, testing, and quality controls related to sensor accuracy.

The FDA action follows an inspection of Abbott’s diabetes care facility in Alameda, California, conducted in October 2025. Inspectors found that Abbott failed to ensure glucose sensor accuracy requirements were transferred to third-party manufacturers and did not adequately monitor in-process and finished devices. The agency also said Abbott released fully assembled and sterilized CGMs without final accuracy testing, relying instead on upstream component-level checks.

The warning letter comes after Abbott recalled around 3 million FreeStyle Libre 3 sensors in November due to incorrect low glucose readings. Abbott said it is implementing corrective actions and providing updates to the FDA. Analysts noted the letter does not restrict Libre sales or manufacturing and is not expected to have a material financial impact.

09-02-2026