Sep. 16--Tens of millions of patients rely on Vytorin to lower their cholesterol.
After a year of bad news for the drug, though, many of those patients are confused and concerned, wondering whether they should continue taking it.
The assault on Vytorin began in January, when a clinical trial claimed that the $3-per-pill drug was no better at sweeping plaque from arteries than a $1-per-pill generic statin. Now the drug is being implicated as a cancer-causer, while facing a congressional inquiry and an investigation by the U.S Food and Drug Administration.
Doctors, meanwhile, must make sense of it all for their patients.
On the issue of Vytorin's effectiveness, some doctors say the study results may not have been as simple as the headlines made them sound. And even if they were, the findings don't apply to the vast majority of their patients.
On the cancer question, many doctors say that the cancer risk has probably been overblown, even though a follow-up study has found a slightly increased risk of cancer deaths among Vytorin users.
With no clear-cut, science-based answers, though, "it is appropriate to raise a note of caution," an editorial in the New England Journal of Medicine said.
Caution appropriate
Caution is fine, but at this point, patients who are taking Vytorin -- a combination of two drugs, Zetia and Zocor -- should continue to take it, said Dr. Elliot Davidson, director of Akron General Medical Center's family medicine residency program.
And he's not just speaking as a doctor, but as a patient, too.
"I actually do take Zetia myself," Davidson said, "so I have a vested interest in making sure it's safe."
Vytorin is targeted to patients who have not been able to reach healthy cholesterol levels with traditional statins, like Zocor, Lipitor or Crestor. For these patients, it's crucial that they continue to take Vytorin, said Dr. Kenneth Berkovitz, Summa Health System's chairman of cardiology.
"We continue to use (Vytorin) as a second-line drug," Berkovitz said. "It does lower cholesterol further than statins alone."
Berkovitz's and Davidson's stance matches that of the American Heart Association and professional groups like the National Lipid Association.
One way to look at the issue, the doctors say, is that the risks of Vytorin -- a product of Merck/Schering-Plough Pharmaceuticals -- are still mostly speculative, while it has long been accepted that high cholesterol is a key risk factor for heart disease.
What is known
So at this point, decisions must be made on what is known, not what is suspected. And what is known, Davidson said, is that Vytorin lowers cholesterol by 18 percent versus the 6 percent response that comes from doubling the dose of a statin.
When the ENHANCE trial questioned Vytorin's effectiveness in January, the message was somewhat muddled, Davidson and Berkovitz said. That trial measured whether the drug cleared plaque from artery walls, not whether it reduced cholesterol. However, the trial involved patients with extremely high cholesterol, so while the drug reduced cholesterol, it didn't clear arteries -- a finding that shouldn't be surprising because even with a reduction, the patients still had cholesterol levels that were too high to expect cleared arteries.
Most of Davidson's and Berkovitz's patients don't have such high cholesterol, so those findings don't apply to them, they said. That study also may not be the best measure.
"We don't care whether the arterial wall gets thicker," Davidson said, "we just don't want them having heart attacks, strokes or deaths."
The cancer question was raised this month by the 2,000-patient SEAS trial, which found 39 cases of cancer among those taking Vytorin (4.1 percent of the patients) and 23 cases of cancer in the group taking a fake medication (2.5 percent of the patients).
The findings were so surprising that a team of Oxford University researchers combed through two other on-going trials, known as the SHARP and IMPROVE-IT studies. Among the 20,000 patients in those two trials, there were 97 cancer deaths among patients taking Vytorin (0.49 percent) and 72 cancer deaths among control patients taking a statin (0.36 percent).
However, the Oxford researchers found essentially the same number of cancers in each group: 313 in the Vytorin group and 326 in the control group.
The studies "do not provide credible evidence of any adverse effect of (Vytorin) on rates of cancer," the Oxford researchers wrote in the New England Journal of Medicine.
Still, the editorial in the same journal said, the increased number of cancer deaths among Vytorin users "should not be assumed to be a chance finding until further data are in."
Tracy Wheeler can be reached at 330-996-3721 or tawheeler@thebeaconjournal.com. To see more of the Akron Beacon Journal, or to subscribe to the newspaper, go to http://www.ohio.com. Copyright (c) 2008, The Akron Beacon Journal, Ohio Distributed by McClatchy-Tribune Information Services. For reprints, email tmsreprints@permissionsgroup.com, call 800-374-7985 or 847-635-6550, send a fax to 847-635-6968, or write to The Permissions Group Inc., 1247 Milwaukee Ave., Suite 303, Glenview, IL 60025, USA.
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