CRESTOR (rosuvastatin calcium) is an inhibitor of HMG-CoA reductase. It has been widely launched for the treatment of patients with dyslipidaemia and has also been approved in the US and EU to slow the progression of atherosclerosis.

Ezetimibe is an anti-hyperlipidemic medication which is used to lower cholesterol levels. Specifically, it appears to bind to a critical mediator of cholesterol absorption, the Niemann-Pick C1-Like 1 (NPC1L1) protein on the gastrointestinal tract epithelial cells as well as in hepatocytes. Ezetimibe is in a class of lipid-lowering compounds that selectively inhibits the intestinal absorption of cholesterol and related phytosterols. Ezetimibe, administered alone is indicated as adjunctive therapy to diet for the reduction of elevated total-C, LDL-C, and Apo B in patients with primary (heterozygous familial and non-familial) hypercholesterolemia. It is also used in combination therapy with HMG-CoA reductase inhibitors. Ezetimibe has a mechanism of action that differs from those of other classes of cholesterol-reducing compounds (HMG-CoA reductase inhibitors, bile acid sequestrants, fibric acid derivatives, and plant stanols). Ezetimibe does not inhibit cholesterol synthesis in the liver, or increase bile acid excretion but instead localizes and appears to act at the brush border of the small intestine and inhibits the absorption of cholesterol, leading to a decrease in the delivery of intestinal cholesterol to the liver. This causes a reduction of hepatic cholesterol stores and an increase in clearance of cholesterol from the blood; this distinct mechanism is complementary to that of HMG-CoA reductase inhibitors.

Atorvastatin calcium (LIPITOR®) is a pyrrole and heptanoic acid derivative, a synthetic lipid-lowering agent. Atorvastatin is a selective, competitive inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase. This enzyme catalyzes the conversion of HMG-CoA to mevalonate, an early and rate-limiting step in cholesterol biosynthesis. Atorvastatin is used to reduce serum levels of LDL(low-density lipoprotein)-cholesterol; apolipoprotein B; and triglycerides and to increase serum levels of HDL(high-density lipoprotein)-cholesterol in the treatment of hyperlipidemias and prevention of cardiovascular disease in patients with multiple risk factors.

Simvastatin is a HMG-CoA Reductase Inhibitor that is FDA approved for the treatment of hypercholesterolemia and for the reduction in the risk of cardiac heart disease mortality and cardiovascular events. It reduces levels of "bad" cholesterol (low-density lipoprotein, or LDL) and triglycerides in the blood, while increasing levels of "good" cholesterol (high-density lipoprotein, or HDL). Common adverse reactions include abdominal pain, constipation, nausea, headache, upper respiratory infection. Cases of myopathy/rhabdomyolysis have been observed with simvastatin co-administered with lipid-modifying doses ( ≥ 1 g/day niacin) of niacin-containing products. The risk of myopathy, including rhabdomyolysis, is increased by concomitant administration of amiodarone, dronedarone, ranolazine, or calcium channel blockers such as verapamil, diltiazem, or amlodipine.