Persistence pays off: FDA OKs Merck’s combo drug

The FDA approved the combo tablet ezetimibe and atorvastatin for the treatment of elevated levels of low-density lipoprotein (LDL) cholesterol in patients with primary or mixed hyperlipidemia.

The tablets, under the brand name Liptruzet (Merck), are an adjunctive therapy to diet when diet alone is not sufficient. Ezetimibe (Zetia, Merck/Schering-Plough) lowers LDL cholesterol by inhibiting the absorption of cholesterol in the digestive tract while atorvastatin affects the production of cholesterol in the liver. Liptruzet is available by prescription only.

The ezetimibe/atorvastatin combination is intended to reduce elevated total cholesterol, LDL cholesterol, apolipoprotein B, triglycerides and non-high-density lipoprotein cholesterol and to increase high-density lipoprotein (HDL) cholesterol in patients with primary (heterozygous familial and non-familial) hyperlipidemia or mixed hyperlipidemia. It also may be used to reduce elevated total cholesterol and LDL cholesterol in patients with homozygous familial hypercholesterolemia.

In March 2012, the FDA rejected Merck's new drug application for the ezetimibe-atorvastatin tablets. In a complete response letter, the agency said it needed additional data.

In a clinical study, the combination tablet lowered LDL cholesterol by 53 to 61 percent, depending on dose. No incremental benefit of the combination drug on cardiovascular morbidity and mortality beyond that demonstrated for atorvastatin has been established.

Atorvastatin may cause myopathy. Rare cases of rhabdomyolysis with acute renal failure secondary to myoglobinuria have been reported with atorvastatin and other statins. A history of renal impairment may be a risk factor for the development of rhabdomyolysis. The concomitant use of higher doses of atorvastatin with certain drugs such as cyclosporine and strong CYP3A4 inhibitors increases the risk of myopathy and rhabdomyolysis.