Is dapagliflozin safe and effective as add-on for patients with type 1 diabetes?

This study looked at the safety and effectiveness of adding dapagliflozin (Forxiga) in poorly controlled type 1 diabetes (T1D). It found that patients treated with dapagliflozin had better blood glucose (sugar) control and more weight loss after 12 months than patients treated with placebo.

Dapagliflozin belongs to a class of medications called sodium-glucose co-transporter 2 (SGLT-2) inhibitors. These medications work by increasing the amount of glucose removed from the body by the kidneys. Dapagliflozin can be used alongside insulin to lower blood sugars in patients with T1D. 

It is important that any treatments given to diabetic patients do not cause weight gain or episodes of dangerously low blood glucose. It is not known if dapagliflozin is safe and effective in these patients long-term.

This study combined the results of two trials. In both trials, participants were divided into 3 groups. Group 1 received 5 mg of dapagliflozin, group 2 received 10 mg of dapagliflozin, and group 3 received a placebo. Each group contained approximately 530 participants. Participants were followed for 12 months to monitor blood sugars, weight, and to check for episodes of low or high blood glucose.

At 6 months, patients treated with dapagliflozin had lower HbA1c (a measure of blood glucose control over the past 2-3 months) levels than the placebo group. Group 1 had a 0.4% reduction in hba1c, group 2 had a 0.43% reduction, and group 3 had no reduction. 

The daily insulin doses decreased in both dapagliflozin groups and were lower than in the placebo group after 1 year. Group 1 and 2 also experienced weight loss. Group 1 lost an average of 2.45 kg and group 2 lost an average of 2.91 kg, while group 3 gained an average of 0.11 kg. 

All groups had a similar number of episodes of low blood glucose. The dapagliflozin groups had an increase in episodes of high blood sugars resulting in diabetic ketoacidosis (DKA) compared to the placebo group. 4% of group 1 participants and 3.5% of group 2 had an episode of DKA, compared to 1.1% of the placebo group.

This study showed that dapagliflozin is effective at lowering blood sugars in patients with poorly controlled T1D while increasing the risk of DKA.

This was a well-designed study. However, it did not include information on diet which might be useful when comparing weight loss and episodes of low/high blood glucose. This study was funded by AstraZeneca, the manufacturer of dapagliflozin.