NEW YORK (Reuters Health) - The addition of exenatide (Byetta), the first in a new class of drugs called incretin mimetics, to a thiazolidinedione (TZD) in type 2 diabetes patients may improve control of blood sugar (glucose). The addition of exenatide to thiazolidinediones (TZDs), drugs such as rosiglitazone or pioglitazone, that increase cell response to insulin, appears to results in better glucose control, researchers report in the Annals of Internal Medicine. Exenatide exerts its regulatory effects by enhancing glucose-dependent insulin secretion, Dr. Bernard Zinman of Mount Sinai Hospital, Toronto and colleagues note. It also slows gastric emptying and reduces food intake.
The researchers studied 233 patients who were receiving TZDs. They were randomly assigned to abdominal injections of exenatide or placebo twice daily.
At 16 weeks exenatide treatment reduced hemoglobin A1C, a marker of blood glucose, by 0.98 percent. It also reduced serum fasting glucose levels and body weight declined by an average of 3.3 lb.
A total of 35 of the exenatide group discontinued treatment. This was due to adverse events in 19 subjects. In the placebo group, 16 discontinued, but only 2 did so because of adverse events.
In all, 40 percent of exenatide patients experienced nausea. This was true of 15 percent of the placebo group.
"Trial duration was relatively short," the investigators concede. Nevertheless, they also point out that during this period exenatide therapy improved glycemic control, and reduced body weight.
In an accompanying editorial, Dr. Saul Malozowski characterizes the trial as "much too short" as well as "much too small" and says that many questions remain unanswered.