Diabetes drug slows atherosclerosis
THE diabetes drug pioglitazone (Actos) slowed the progression of atherosclerosis and showed other cardiovascular benefits in a recent head-to-head clinical trial against glimepiride (Amaryl).
Known as PERISCOPE, the study enrolled 543 type 2 diabetics with coronary disease. They were randomly assigned to receive either 1-4 mg glimepiride or 15-45 mg pioglitazone, titrated to maximum tolerable dosage. The amount of arterial plaque was measured with intravascular ultrasound at baseline and 18 months later, and the change in the percent atheroma volume (PAV) was calculated. PAV decreased 0.16% with pioglitazone and increased 0.73% with glimepiride.
“This is the first demonstration of the ability of any hypoglycemic agent to slow the progression of coronary atherosclerosis in patients with diabetes,” the researchers report (JAMA. 2008;299:1561-1573).
An accompanying editorial says that the PAV range was very small (<1%). However, that is “well within the range of what is achieved with some therapies demonstrated to improve cardiovascular outcomes, such as high-dose statins,” the editorial says (JAMA. 2008;299: 1603-1604).
Mean baseline glycosylated hemoglobin (HbA1c) levels were 7.4% in both groups, but they declined slightly more (-0.55% ) with pioglitazone than with glimepiride (-0.36%). Pioglitazone was also more effective in raising the “good cholesterol” HDL (by 5.7 mg/dL vs. 0.9 mg/dL) and lowering median triglycerides (-16.3 mg/dL vs. +3.3 mg/dL). In addition to changes in HbA1c levels, insulin levels, other lipid paramteters, and BP were all more favorable in patients treated with pioglitazone.