In what is described as the largest diabetes-prevention trial ever conducted, Avandia (rosiglitazone) reduced the risk of developing type 2 diabetes by 62% relative to placebo among people at high risk of developing type 2 diabetes. The trial combined the treatment with counseling on healthy eating and exercise.
The trial evaluated the likelihood of progression to type 2 diabetes over a three-year period among 5,269 people with a condition known as “pre-diabetes.” In pre-diabetes, blood sugar levels are higher than normal, but not yet high enough for a diagnosis of type 2 diabetes.
In this study, designed and conducted by the Population Health Research Institute at McMaster University, 10.6% of people receiving Avandia progressed to type 2 diabetes versus 25% of people treated with placebo.
Avandia also normalized blood sugar levels for 51% of people thus, people taking rosiglitazone were about 70% more likely than those taking placebo to return to normal blood sugar levels. As might be expected, people in the placebo group with higher Body Mass Index (BMI), an indicator of obesity, were more likely than those with lower BMI to progress to diabetes. These findings suggest that Avandia may reduce the increased risk of developing diabetes that is attributable to obesity.
“The findings are particularly significant as we are in the midst of an epidemic of type 2 diabetes with global implications. It is also noteworthy that the damaging complications of type 2 diabetes can often precede the diagnosis of this condition by several years,” said Dr Bernard Zinman, professor of medicine, University of Toronto. “By demonstrating that rosiglitazone significantly reduced the risk of developing type 2 diabetes, these data provide important evidence that it may be possible to alter the course of rising blood sugar levels and its consequences.”
However Avandia has been shown to increase the risk of non-fatal heart failure and bodyweight also increased in the Avandia group compared to placebo. Data presented by McMaster University showed that all cases of heart failure were treated effectively during the trial
Rosiglitazone is an approved treatment for type 2 diabetes that improves blood sugar control, enabling people to reach recommended blood sugar levels. No agent including rosiglitazone is currently approved for the treatment of pre-diabetes 5.
Pre-diabetes is estimated to affect 300 million people globally.