Schering-Plough, the company that makes Zetia and Vytorin (simvastatin combined with Zetia), released the results of the ENHANCE trial. The trial looked at simvastatin 80 mg versus simvastatin 80 mg plus Zetia 10 mg and the effects on carotid intima medial thickening, in other words, the lining of the carotid artery. The addition of Zetia had no beneficial effect.
I think that the intent of Schering-Plough was to demonstrate that not only is Zetia good at lowering LDL cholesterol, but that it also has a beneficial effect on the lining of the arteries, and therefore can protect against cardiovascular events. Clearly, the study fell short.
I've gotten phone calls and e-mails from patients on Zetia asking, should I stop taking Zetia? Does it matter if my cholesterol is lowered?
The bottom line is this: There is great data for statins, particularly simvastatin (Zocor) and atorvastatin (Lipitor) for lowering cholesterol and reducing event rates. With these medications, we know that lower cholesterol is better, with an optimal LDL goal of 60-70. And, I think that this new study lends credibility to the theory that it does matter what class of drugs are used to lower cholesterol, that it's not just the cholesterol lowering effect of the statins that make them so effective, it's also the effect on the arteries' lining.
However, some people cannot tolerate statin medications due to muscle aches or liver function problems. For these patients, Zetia might be an appropriate alternative.
If you're taking Zetia or Vytorin, please do not stop your medicine. Talk to your doctor. If you are on Zetia alone, you may ask if you should be on a statin instead. There may be good reason why you are on Zetia.