There are many cholesterol-lowering drugs on the market today, and for the last several years one of the most popular has been Vytorin. Vytorin is actually a combination of two other cholesterol medications, Zetia and Zocor. Unfortunately, recent clinical findings have linked Vytorin to a number of serious side effects including myopathy, kidney damage and rhabdomyolysis.
Vytorin is a combination drug composed of Zocor (simvastatin) and Zetia (ezetimibe) that has been on the U.S. market since 2004. Zocor works in the liver to reduce cholesterol, while Zetia is a non-statin prescription medication that works in the digestive tract. Vytorin is manufactured and marketed jointly by Schering-Plough and Merck, the same company that made Vioxx, a painkiller pulled from the market in 2004 because of an increased risk of heart attack and stroke. Since first being approved, Vytorin has been widely prescribed and has generated billions in sales in the United States.
Side Effects of Vytorin
Though Vytorin may be effective at lowering the risk of heart disease by lowering cholesterol, studies have shown that the drug can also lower inflammatory factors that can aggravate plaques, causing them to burst and block arteries, as well as reduce triglycerides, an extremely dangerous form of fat for the heart. Vytorin has been associated with the following serious side effects:
- muscle damage
- kidney damage
- kidney failure
Recently, the U.S. Food & Drug Administration (FDA) warned of the potential link between Vytorin and the development of rhabdomyolysis, a painful muscle condition where skeletal muscle breaks down, potentially leading to fatal consequences. As the muscles are broken down, they release a protein called myoglobin, which has been known to cause severe kidney damage. Making the disease more difficult to detect, rhabdomyolysis may not cause any symptoms at all. If they do occur, signs and symptoms may include:
- muscle aches and pain;
- darkening of the urine color – myoglobin is released from the muscles when they break down, and this can cause a red or cola color of the urine.
The treatment of rhabdomyolysis depends on its cause and severity. If Vytorin is found to be the cause of the disease, it is addressed by discontinuing the toxic medication. In severe cases of rhabdomyolysis, hospitalization may be required.
Vytorin ENHANCE Study
Merck and Schering-Plough have come under fire for allegedly making false claims in their marketing campaign for Vytorin. New York Attorney-General Andrew Cuomo is currently investigating whether the companies violated the state’s laws regarding false advertising. Specifically, officials are concerned that despite results from the 2008 ENHANCE study which found that Vytorin was no more effective than the generic simvastatin, the drug was marketed as such. Many familiar with these issues believe that as early as 2006, both Merck and Schering-Plough knew that Vytorin was no more effective in reducing plaque than simvastatin, which is manufactured at 1/6 the cost.
The ENHANCE study found that while Vytorin reduced levels of bad cholesterol (low-density lipoproteins, LDLs), the drug had little effect on the buildup of plaque in the arteries, a condition that leads to heart attacks and strokes. These findings raised red flags for many experts.
“The fact that the trial showed a huge LDL reduction, and that things were still going the wrong way [in terms of plaque buildup] is stunning,” says Dr. Steven Nissen, chairman of cardiovascular medicine at the Cleveland Clinic and an outspoken critic of the delay in the release of the study results. “This study shows that it matters how you lower cholesterol, not just how much you lower cholesterol. The bottom line is that we just don’t know what Vytorin does, because we don’t have the clinical trials. We know Vytorin blocks absorption of cholesterol. But what else does it block — something else in the diet that could be beneficial? We just don’t understand fully how it works.”
As for the two year delay in reporting the results of the ENHANCE study, a Schering-Plough spokesperson told TIME magazine that it was due to the complexity involved in interpreting the tens of thousands of images of the carotid arteries that the study generated. The long delay prompted the House Energy and Commerce Committee to send a letter to both Merck and Schering-Plough requesting the results of the research, noting that the end point of the companies’ original study design had been suspiciously changed in the form submitted to the government’s clinical trials database in October 2007. “We are concerned … with the apparent manipulation of trial data,” the letter read.