Adding Byetta to oral treatment improves control for type 2 diabetes.
Byetta (Exenatide), an injected drug for type 2 diabetes, has been approved by the FDA for use in combination with orally administered diabetes drugs. Byetta is prescribed for people who have not achieved optimal glycemic control with metformin, sulfonylurea drugs, or combined metformin-sulfonylurea therapy. In a study of 336 people with inadequately controlled type 2 diabetes, researchers randomly assigned half of the group to self-administered injections of Byetta twice a day at a dose of either 5 or 10 micrograms. The other participants administered inactive placebo injections. Both groups continued to take metformin. The Byetta study was reported in the Journal Diabetes Care.
After 30 weeks, HbA1c levels were at or below 7% in 46% of people who took the higher dose of Byetta and in 32% of those who took the lower dose. (The HbA1c test measures the amount of glucose attached to hemoglobin – the oxygen-carrying protein in red blood cells that gives blood its color.) Only 13% of people taking placebo injections achieved this HbA1c goal. Unlike many other diabetes drugs, Byetta did not cause weight gain, but rather Byetta produced an average weight loss of 3–6 pounds during the 30 weeks. A second study showed similar results with Byetta injections in 733 people with type 2 diabetes who failed to achieve adequate glycemic control while using combined metformin-sulfonylurea treatment at maximally effective doses.
The result of the Byetta study is good news for people with type 2 diabetes who are advised to keep their daily fluctuations in blood sugar as close to normal as possible. This advice is given because of the wealth of scientific data from two large studies that concluded in the 1990s: the Diabetes Control and Complications Trial (DCCT) and the United Kingdom Prospective Diabetes Study (UKPDS).
The findings of these studies have had an impact on diabetes treatment ever since. The DCCT and UKPDS told us that tight control of blood sugar—keeping it as close to the normal range as possible—slashes the risk for long-term damage to very small blood vessels. These so-called microvascular complications include vision loss, (retinopathy), damage to nerves (neuropathy), and damage to the kidney (nephropathy). Tight blood sugar control can reduce the risk for microvascular complications by roughly 25–75% or more.
