The Enhance Trial Revisited
There has been some confusion surrounding the reporting of results from the Enhance Trial. As you know, the results from this study showed that the cholesterol-lowering drug Vytorin—a combination of Zetia and Zocor (a statin) —was no better than a generic version of Zocor by itself at controlling atherosclerosis.
In the Enhance clinical trial, 720 patients were treated with Vytorin or a generic version of Zocor and the amount of plaque that accumulated in the arteries of both groups was assessed by blood vessel imaging. Because Vytorin lowers LDL-cholesterol more than Zocor alone, both Schering –Plough and Merck (the companies that sponsored the trial) expected the patients who took Vytorin to have less growth of plaque in their arteries than those who took generic Zocor alone. As we all now know, this was not the case. In fact, there are some data which suggests that Vytorin treatment may actually enhance or promote plaque deposition and growth.
Since arterial plaque is closely associated with heart attack and stroke, the results from the Enhance trial led some to suggest that Vytorin doesn’t work any better than Zocor at preventing heart attack or stroke. While this may prove to be the case, there are currently no data to substantiate or refute this assertion. Those data will be generated in planned outcome trials that will measure the incidence of heart attack and stroke in patients taking Vytorin or Zocor. Merck and Schering-Plough began enrolling patients for these studies in 2006 and don’t expect any results before 2012. This may be too little, too late.
Merck and Schering have come under fire for not releasing the results from the Enhance trial in a timely fashion. A Congressional committee investigating the Vytorin controversy alleges that Merck and Schering Plough executives knew about the results of the Enhance studies at least two years before they released the data. The companies repeatedly delayed releasing the results of the trial, however, saying publicly that many of the images of the arteries were unclear and might need to be re-examined. Both companies have also have been criticized for delaying the initiation of the planned outcomes trials.
Shares of Merck and Schering-Plough plummeted yesterday following Sunday’s announcement at the American College of Cardiology meeting in Chicago.
Until next time….
Good Luck and Good Job Hunting (avoid NJ)!!!!!!!!!
