Abbott is preparing to launch Libre Duo, its first sensor that combines glucose and ketone measurement, after the device received the CE mark in Europe and the company submitted an application to the U.S. Food and Drug Administration (FDA). Abbott expects a U.S. decision before the end of 2026, while the system will begin launching in some European countries during the same year.
The device is intended to enable continuous ketone measurement alongside glucose monitoring, with the aim of helping some people with diabetes detect indicators that may be associated with diabetic ketoacidosis (DKA) and act earlier. However, endocrinologists and diabetes experts who spoke with MedTech Dive say that expanding access to this data alone will not resolve how to interpret it or what actions are appropriate when levels rise.
Who might use the sensor?
Abbott plans to offer a 15-day European version for adults and a 10-day version for people aged 2 years and older. Libre Duo is expected to serve people with type 1 or type 2 diabetes who are at greater risk of diabetic ketoacidosis, including those who use insulin or other glucose-lowering medications.
In the United States, however, the FDA has not yet determined which groups will be able to use the device, as the application remains under review. Alisa Schiffman, Abbott Diabetes Care’s senior medical director and a pediatric endocrinologist, said the company hopes to obtain authorization allowing Libre Duo to be used by people with diabetes who are at risk of diabetic ketoacidosis.
What is the practical benefit of continuous ketone measurement?
Doctors note that many people with diabetes do not measure ketones regularly or do not keep the necessary tools on hand. Urine tests are currently the most common method, but they may lag behind what is happening in the body. Blood tests provide a more convenient measurement, but insurance coverage for them is limited, according to Brynn Marks, senior vice president of medical affairs at the nonprofit Breakthrough T1D.
A ketone reading when glucose is high may help distinguish a meal-related rise from a more serious problem, such as an insulin pump set failure caused by a blocked tube or the set coming out of place. However, Rayhan Lal, an assistant professor and endocrinologist at Stanford Health Care, cautioned against viewing ketones as a direct substitute for measuring insulin deficiency. Ketones are a product of fat metabolism, and their elevation is not specific enough to identify the cause on its own.
Lal believes that directly measuring insulin would be more useful in evaluating pump-set failure, but adding ketones to existing glucose sensors is technically easier than developing a practical method for measuring insulin.
How can users avoid being overwhelmed by data?
Continuous glucose monitoring devices provide a large amount of information, and adding ketones could increase the burden on users if alerts are not designed carefully. Abbott has not disclosed details of the Libre Duo interface or alert mechanism, but Schiffman said glucose will remain “the foundation,” while ketones will appear when needed.
Schiffman compared glucose to the speedometer that a driver monitors continuously, and ketones to the check-engine light that signals that something requires attention. Diana Isaacs, director of diabetes technology education and training at Cleveland Clinic, believes that ketones do not change as quickly as glucose; therefore, a reading every five minutes may not be necessary, while a reading every few hours could be useful instead of resorting to a laboratory test or a separate fingerstick.
Why is a reading alone not enough to make a decision?
According to experts, there is no single way to respond to every elevated reading; the decision depends on the individual, the nature of their condition, and their care provider’s instructions. Breakthrough T1D led an international consensus recommendation published in the journal Lancet in January, defining normal, elevated, and high levels, with 3 millimoles per liter considered a high level requiring urgent intervention. But it acknowledged that evidence for using this number as a diagnostic threshold for diabetic ketoacidosis is limited.
Individualized thresholds may be more appropriate based on age, medications, and food, while trend arrows can show whether ketones are rising or falling. When ketones are elevated, a user may consider whether a dose was missed, whether an illness led to reduced food intake, or whether there is a problem with the tubing of an automated insulin-delivery system. However, experts cautioned against interpreting the number outside its context; Lal saw a child who met a protocol’s criteria for action despite receiving enough insulin because prolonged physical activity was an influential factor. In another case, the increase was slight, but the person had an insulin deficiency, which changed the meaning of the reading.
What remains unresolved?
Groups of diabetes experts are working on general guidance for patients and caregivers, while current protocols, including the Yale University School of Medicine’s pediatric clinic protocol, need to be updated to accommodate continuous ketone monitoring.
Abbott has also not announced the price of Libre Duo or details of its insurance coverage. Some current Libre devices cost at least $75 out of pocket, according to Isaacs, but adding a cost to the new sensor could affect how widely users adopt it compared with other devices. Abbott said it will work with insurers and payers after the device receives FDA approval. Therefore, Libre Duo’s practical impact depends on three factors that have not yet been resolved: the scope of U.S. authorization, the clarity of the guidance, and affordability.