Liptruzet, a cholesterol-lowering drug that combines Merck’s Zetia (ezetimibe) with atorvastatin (generic version of Pfizer’s Lipitor) has been approved by the US FDA (Food and Drug Administration).
According to Merck and Co, Liptruzet tablets are for the treatment of high LDL (low-density lipoprotein) cholesterol in patients with primary or mixed hyperlipidemia alongside a special diet when diet alone is not enough. Hyperlipidemia is an excessively high concentration of fats (lipids) in the blood. LDL is also known as “bad cholesterol”, as opposed to HDL (the good one – high-density lipoprotein).
According to Merck, Liptruzet contains ezetimibe, an effective drug for lowering LDL cholesterol, plus atorvastatin, a commonly prescribed statin.
Merck says Liptruzet treats two sources of cholesterol:
- with atorvastatin it reduces the production of cholesterol in the liver
- with ezetimibe it inhibits the absorption of cholesterol in the digestive tract
Merck quotes Peter H. Jones, M.D., associate professor of medicine, Baylor College of Medicine, who said “A significant percentage of patients are unable to lower their LDL cholesterol to recommended levels despite treatment. Along with a healthy diet, Liptruzet (ezetimibe and atorvastatin) is an effective new lipid-lowering treatment option that may help address this unmet need as the complementary actions of its components can provide significant additional LDL lowering beyond atorvastatin therapy alone.”
Merck admits that Liptruzet has not been shown to lower the risk of cardiovascular disease, including stroke and heart attack. Given this fact, some cardiologists cannot understand why Liptruzet has been approved.
The New York Times quotes Dr. Steven Nissen, chairman of the department of cardiovascular medicine at the Cleveland Clinic as saying “This (Liptruzet’s approval) is extremely surprising and disturbing”.
Forbes quotes Dr. Nissen as saying:
“It does not make any sense. I find it astonishing that after all the controversy about ezetimibe the FDA would approve another combination product with a drug that has been on the market for a decade and has not been shown to improve cardiovascular outcomes. It seems like the agency is just tone deaf to the concerns raised by many members of the community about approving drugs with surrogate endpoints like cholesterol without evidence of a benefit for the disease we are truly trying to treat – cardiovascular disease.”
Many experts expected the FDA to wait for the results of a major study comparing the ezetimibe plus simvastating combination to simvastatin alone for preventing cardiovascular events and deaths before deciding on whether to approve Liptruzet. The study is not due to be completed until the end of 2014.
Dr. Nissen explained that if doctors really want an ezetimibe/atorvastatin combo they can prescribe them separately anyway. Approving the Liptruzet combination pill risks “letting the genie out of the bottle” – it could become widely used, only to be found not to prevent cardiovascular events at some future date.
Liptruzet is taken once daily as a pill, and is sold in doses of 10 milligrams of ezetimibe plus 10, 20, 40 or 80 milligrams of atorvastatin. Merck says Liptruzet will be sold at $5.50 per pill. It is not yet known whether insurance companies plan to cover the medication.
Sales of Zetia (ezetimibe) have dropped since 2007, but it is still among Merck’s “blockbuster” medications. Last year, Zetia’s global sales reached $2.6 billion.
In September 2011, the German Institute for Quality and Efficiency in Health Care revealed that there is lack of proof that patients who take ezetimibe plus statins have a lower risk of heart attacks.
Health researchers from the University of Virginia Health System wrote in the journal Atherosclerosis (May 2011 issue) that ezetimibe may not halt atherosclerosis (significant artery wall thickening) in some patients. Despite ezetimibe’s ability to lower LDL cholesterol, the scientists detected a “notable progression of atherosclerosis” among patients who were prescribed a combination of ezetimibe plus a cholesterol-lowering statin. The article followed two major clinical studies in 2008 and 2009 that also questioned the benefits of ezetimibe.
Written by Christian Nordqvist