So what is the deal with Zocor (Simvastatin), Zetia (Ezetimibe), and Vytorin(Simvastatin + Ezetimibe)?  Over the past couple of months, there has been extensive media coverage about an unpublished study at the New England Journal of Medicine about Comparing Vytorin with Zocor.  Without going into extensive details, there was no difference between the two drugs when looking at the thickness of the carotid artery, called intima-media thickness (IMT, a measure of atherosclerosis).  So what?

 Well, Vytorin, which is a combination of Zetia and Zocor, is a powerful medication when it comes to lowering of the blood cholesterol level, specifically the LDL.  So, it goes without saying that the authors of the study expected that this will result in a reduction in the atherosclerosis in the selected patients with familial hypercholestrolemia (FH).  Today, the final results of the study were finally published and presented at the American College of Cardiology.  Thus, the renewed media interest and the flood of calls from frantic patients to their pharmacies and doctors.  One patient asked me, "Zocor is off the market, what should I take now?". 

 Of course, Zocor is NOT off the market nor are Zetia or Vytorin.  In fact, there is no new data on the effectiveness of Zocor.  The ENHANCE Study, which only included patients with a familial form of hypercholesterolemia, concludes that there is no difference in the intima-media thickness of the carotid artery between the group that took zocor alone versus the group that took the combination of zocor and zetia (vytorin), despite significant lowering of LDL and C-reactive protein in the Vytorin group.  So what does this mean?  Should I stop taking my medication if I am taking one of these medications?

 The best recommendation is: do not panic.  This study did not show any harm.  At its worse, the study tells you there may be no additional benefit when taking Vytorin versus Zocor alone.  Also, don't stop any medication on your own, before talking to your doctor.  Ultimately, the goal of any cholesterol lowering medication is to prevent cardiovascular events, such as strokes, heart attacks, or death.  This study does not address any of those end points.  Finally, keep in mind that any new study that has a conclusion contrary to the current knowledge, needs to be verified and reproduced with other larger studies.  There are many reasons, other than "zetia doesn't work", that could explain these findings.  There may have been too few patients in the study, the patients in the study may not have had a severe enough disease to show a difference, the study may not have gone on for long enough to result in a meaningful difference, or, the combination may actually reduce heart attacks and strokes despite no reductions in the intima-media thickness.  There simply needs to be more data...