Merck and Schering-Plough’s ENHANCE comparator trial for Vytorin did not meet its primary endpoint. The trial examined Vytorin—which combines the companies’ drug Zetia (ezetimibe) with Merck’s Zocor (simvastatin)—against Zocor alone in demonstrating plaque regression and cholesterol lowering, in a set of patients with a rare condition.     The ENHANCE trial was conducted in 720 patients with Heterozygous Familial Hypercholesterolemia (HeFH), a rare genetic predisposition to ...