Can exenatide once weekly reduce diabetic kidney damage?

This study looked at exenatide (Byetta) for patients with type 2 diabetes (T2D) and kidney damage. It found that exenatide may reduce kidney damage compared to other diabetes treatments.

T2D is a disorder in which the body does not respond well to the hormone insulin. This causes high levels of glucose (sugar) in the blood. Diabetes can lead to complications including kidney damage.

Kidney function can be measured by estimated glomerular filtration rate (eGFR), or how quickly the kidneys can filter blood. When the kidneys are damaged, proteins including albumin can pass from the blood into the urine. This is measured by the urine albumin to creatinine ratio (uACR).

Exenatide is a diabetes medication. Exenatide mimics a hormone the gut released after eating and increases the amount of insulin the body releases. Past studies have found that exenatide improves blood glucose control and can help reduce body weight. However, it is unclear whether exenatide reduces kidney damage in patients with T2D.

This analysis included six phase III studies of patients with T2D and albumin in the urine (uACR over 30 mg/g). 674 patients started the studies, and 468 patients remained through week 26 or 28 of the study. 194 of these patients took exenatide, and 274 used a different treatment. The studies used either insulin or oral diabetes medication as a comparison treatment. 

Albumin in the urine decreased more in the exenatide group compared to other treatments (uACR reduction of 55.5% vs. 39.7%). Studies that used insulin as a comparison treatment had similar results to those which used oral medications. Patients with early kidney disease (uACR between 30 and 300 mg/g) had more benefit from exenatide than patients with more pronounced kidney disease (uACR over 300 mg/g). 

Glycated hemoglobin (HbA1c) is an estimate of glucose control over the previous two to three months. Glucose control improved significantly more for the exenatide group (HbA1c reduction of 1.4% vs. 1.0%). Patients taking exenatide lost an average of 2.3 kg (5.1 lbs), whereas patients taking comparison treatments gained an average of 0.5 kg (1.1 lb).

Both groups had a low rate of serious side effects. Patients taking exenatide were more likely to experience gastrointestinal side effects (34.9% vs. 17.9%).

This study found that exenatide may improve kidney function in patients with diabetes.

The studies used in this analysis were not designed to test for the effect of exenatide on kidney disease. These results need to be confirmed with additional studies. This study was funded by AstraZeneca, the manufacturer of Byetta.