Merck presented data Monday showing its Vytorin cholesterol treatment performing well in several studies. Merck ( MRK) released a new analysis of three studies that it says shows Vytorin reduced LDL, or "bad," cholesterol by an average of 52.5% in patients with high cholesterol. The company said the same analysis found its other cholesterol drug, Zocor, showed an average reduction of 38%. Merck's analysis pooled data from three similar randomized studies that included a total of 3,083 patients with primary hypercholesterolemia. The study also measured a risk factor for cardiovascular disease called "C-reactive protein," or CRP. A pooled analysis across all doses of Vytorin and Zocor found geometric mean CRP levels declined in patients taking Vytorin by 31% as compared to a 14.3% reduction in the group of patients taking Zocor. The results were presented Monday at the 55th Annual Scientific Session of the American College of Cardiology.