So far, it's been a tough sale. But it's also offered an illuminating look at how drug companies push new drugs, which are often approved despite the absence of proof that the treatments actually help patients -- not to mention the ways Big Pharma can obstruct or delay studies that might dampen physicians' enthusiasm for writing more prescriptions.
No relief for clogged arteries
Over the weekend, a panel of heart specialists at the annual meeting of the American College of Cardiology criticized both drugs -- Zetia, a Schering-Plough cholesterol drug intended as an alternative to older but frequently prescribed drugs called statins, and Vytorin, a combination of Zetia and an older Merck statin called Zocor -- and said doctors should sharply cut back their use. That would hurt quite a bit: Sales of the two drugs reached $5.1 billion last year, more than double what they pulled in just two years earlier.
That panel followed the formal presentation of data from a trial in 720 patients that essentially showed Zetia failed to reduce the thickness of arteries in the neck, a proxy for the risk of stroke and heart attack. (The test actually compared Vytorin to Zocor alone.) "Whatever way you look at the data, the addition of [Zetia] made no difference," said John Kastelein, the Dutch researcher who oversaw the study.
The trial, known as Enhance, was just published in the New England Journal of Medicine, which also ran two editorials urging doctors to prescribe the drugs cautiously. A second report, also published in the NEJM, described how use of Zetia and Vytorin have skyrocketed in the U.S. since 2002, despite the lack of evidence that the drugs' cholesterol-lowering effects do patients much good. Usage in Canada, where direct-to-consumer advertising is illegal, rose much more slowly over the same period.
How not to win friends and influence doctors
Merck and Schering have tried to argue, so far without much success, that the negative results mainly reflected the fact that many trial volunteers had taken statins for years prior to the test, making further improvements due to Zetia harder to see. Further study might clear up that point, but the next big trial isn't due to report results until 2012 -- largely because researchers just decided to boost its size to take a more detailed look at Zetia's effects.
But the companies have had an even harder time deflecting concerns that they obstructed and meddled with the Enhance trial, which Kastelein has suggested could have been published a full year earlier.
Merck and Schering now face at least two congressional probes into Enhance and their marketing of the two drugs. Investigators at the Senate Finance Committee, in fact, have just released the text of several angry emails Kastelein wrote to a Schering executive as delays mounted. "This starts smelling like extending the publication for no other (than) political reasons and I cannot live with that," the researcher wrote in one note. "[Y]ou will be seen as a company that tries to hide something and I will be perceived as being in bed with you!" read another. (Hat tip to Ed Silverman at Pharmalot, who first reported the email release.)
Congressional investigators are also looking into contributions from the two companies to the cardiology association, which initially asked its members to withhold judgment after the companies released preliminary data from Enhance in January, as well as other efforts to drum up doctor excitement for the drugs. Schering's "49 Plan," for instance, aimed to spend $3.5 million over seven weeks -- 49 days, get it? -- schmoozing physicians over lunch and dinner in order to talk up Zetia.
However this all turns out, one thing is clear: It's far too easy for pharmaceutical companies to create outsized demand for drugs of questionable benefit, and to subordinate the scientific information doctors need about new drugs to marketing concerns. I'd like to think that the Vytorin saga might actually chasten Big Pharma into curbing its aggressive marketing practices, but so far there's little to suggest that the industry won't just take its lumps and then go right back to business as usual.
UPDATE: The text of Kastelein's emails turned out to be embedded in a lettter Republican Sen. Charles Grassley sent to Merck and Schering-Plough yesterday (PDF link), which the Finance Committee has posted on its Web site.