Behind the headlines this week about how two of the biggest selling drugs in the world have bombed is an interesting tale of how and why drugs are developed, tested, and sold.

Zetia and Vytorin, a combination of the old statin Zocor and Zetia, came on the market like blockbusters,  even though they had not been extensively studied. The Food and Drug Administration does not require a lot of those kinds of studies because the link between low density cholesterol and heart disease is medical gospel.  Zetia had been studied in only a few thousand patients before it was approved, but doctors and patients loved it because it could bring cholesterol down without the same unpleasant side affects (muscle pain, bloating, gastrointestinal problems) that come with other cholesterol lowering drugs, especially when given in high doses.  

The study, a hot topic at the American College of Cardiology conference in Chicago this week, found that Zetia lowered cholesterol all right. But it did nothing to reduce the amount of fatty plaque that causes heart attacks and strokes. In fact, it made it worse. 

But that’s not what made the doctors mad.  The cardiology conference was in an uproar because the doctors believed the drug companies that make the Zetia and Vytorin (Merck and Schering-Plough) sat on that information for more than a year. (The companies dispute that.) Meanwhile, they continued to market and sell the drug to millions of people, generating sales of $5 billion last year.

The good news is that the drugs apparently do no harm to the people who take them. For reasons that no one understands at this point they just don’t seem to do any good.

Now the big questions remain: Is medical gospel wrong? Is there a limit to how much lowering cholesterol can help? Does Zetia prevent heart attacks and stroke? We won’t know the answers to those an other questions until the long-term outcomes study on Zetia is completed in 2012 or so.

Should you stop taking Zetia or Vytorin if you take them now?  Well, say doctors, that depends. Experts at the conference said they should only be taken as a last resort if nothing else works.

So once again, it’s up to you and your doctor to figure it out.

And stay tuned. The cardiology conference is just beginning.

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