Why The Market's Up, But Merck's Down

On a day when the market is in full-tilt rally mode on the GDP number, shares of Dow component Merck and the company it's buying, Schering-Plough , are sliding. So, what gives?

Well, Bernstein analyst Dr. Tim Anderson put out a MRK-SGP research note this morning titled, "Caveat Emptor," and he did a voicemail blast to clients this morning saying he was "sounding the alarm bells once again."

He's writing and talking about the upcoming presentation of data from a study called "Arbiter 6" comparing MRK and SGP's cholesterol-fighter Zetia to Niaspan from Abbott Labs . Zetia is also used to make Vytorin along with the statin Zocor. They're big-selling drugs. Researchers will unveil the study results in a so-called "late-breaking clinical trial" session at the American Heart Association's annual meeting in Orlando on Monday, November 16th, at 10:45 a.m. ET. A "late breaker" is prominent, prestigious status that scientific and medical meetings typically grant to big, important studies. They're often done in the biggest convention hall before the largest audience.

Dr. Anderson also says the study will be published simultaneously in a major medical journal, most likely the "New England Journal of Medicine," along with an editorial or two. And he says one of the opinion pieces will be "pretty scathing by a well-known critic." Any guesses? Hmm, lemme think.

Dr. Anderson doesn't think there's anything, as he put it, "truly wrong" with Zetia or Vytorin, but for whatever reason he believes the drugs are "being attacked by some pretty fierce critics." Long-term he still likes Merck together with Schering, but in the near-term he says, "Buyer beware."

On Merck's most recent conference call company officials were already revving up the spin machine. They promised that they will be at AHA in full force messaging docs, so-called key opinion leaders and, of course, the media. I wonder if they'll send the big guns to talk to us.

Disclosures: Someone who lives with one of the Bernstein pharma researchers owns Merck stock. And a part of Bernstein owns at least one percent of MRK and SGP shares.

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