CNNMoney.com at http://money.cnn.com/news/newsfeeds/articles/djf500/200807031304DOWJONESDJONLINE000719_FORTUNE5.htm
New Pfizer Lipitor Study Could Fuel Cholesterol-Drug Debate
July 03, 2008: 01:04 PM EST
A study showing
Pfizer Inc.'s (PFE) cholesterol drug Lipitor was no better than a fake pill in
slowing artery thickening has raised questions about the imaging technique used in that trial - and in a previous study that
caused sales of rival drug Vytorin to fall.
The results of the so-called Cashmere study were unexpected
because previous studies have shown that Lipitor, the world's best-selling prescription drug, reduces the risk of heart attacks
and cardiovascular events.
"The question is not the agent in this study because we know Lipitor works," BMO
Capital Markets analyst Robert Hazlett said.
Instead, Hazlett said it raises questions about the reliability of the study's imaging
technique when used in certain patient populations. Hazlett recently discovered the study's results on the Web site clinicalstudyresults.org
and issued a research note about the trial Thursday.
Interestingly, the new Lipitor data provides ammunition to defenders of rival cholesterol
drugs Vytorin and Zetia, which are marketed by a joint venture of Merck & Co. (MRK)
and Schering-Plough Corp. (SGP). The Cashmere study's design used
the same imaging technique as the "Enhance" study of Vytorin, which showed Vytorin was no better than the statin drug simvastatin
at slowing artery thickening.
Merck and Schering-Plough have defended Vytorin's effectiveness in lowering bad cholesterol
levels, but prescription volumes for both Vytorin and Zetia have plummeted since Enhance results were released in January.
Vytorin is a combination of Zetia and simvastatin.
In both studies, patients at the start of the trial had relatively low artery disease
burden, possibly because of prior treatment with cholesterol drugs. That could help explain why the study drugs were unable
to show a significant benefit as measured by an imaging technique known as carotid intima-media thickness, or CIMT,
a noninvasive ultrasound test.
Merck recently discontinued a separate CIMT trial
of an experimental cholesterol drug, MK-524A, saying the imaging technique wasn't appropriate for the study's patient population.
One key difference between Lipitor and Vytorin, however, is that there are still
no data proving that Vytorin reduces the risk of heart attacks more than simvastatin alone, whereas Lipitor's benefit in that
regard has been proven in past trials. A large trial designed to test Vytorin's effect on outcomes is several years away from
completion.
Spokespeople for New York-based Pfizer couldn't immediately be reached Thursday morning.
Lipitor is crucial to Pfizer's fortunes. It generated $12.7 billion in sales last
year, roughly one-fourth of total company revenue. Lipitor sales have been under pressure mainly because of the 2006 introduction
of generic versions of simvastatin, which was previously a blockbuster drug for Merck under the brand Zocor.
Also, Pfizer recently halted television ads for Lipitor following criticism that
the doctor featured in the ads wasn't licensed to practice. Pfizer recently agreed to settle patent litigation that is expected
to keep generic Lipitor copycats off the U.S. market until
2011.
The Cashmere study evaluated the effect of Lipitor on CIMT in nearly 400 post-
menopausal women with moderately high levels of bad cholesterol. Roughly half were given an 80-milligram dose of Lipitor -
the highest available dose - daily for up to 12 months, and the other half took a fake pill, or placebo. Patients' artery
thickness was measured at the beginning and end of treatment by CIMT tests.
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New
York Times, The Diabetes Dilemma for Statin
Users By ERIC J. TOPOL, Published: March 05, 2012 http://mobile.nytimes.com/article?a=920989&f=28⊂=Contributor
San Diego, Calif.
We're overdosing on cholesterol-lowering
statins, and the consequence could be a sharp increase in the incidence of Type
2 diabetes.
This past week, the Food and Drug Administration raised questions
about the side effects of these drugs and developed new labels for these
medications that will now warn of the risk of diabetes and memory loss. The announcement said the risk was
"small" and should not materially affect the use of these
medications. The data are somewhat ambiguous for memory loss. But the magnitude of the problem for
diabetes becomes much more apparent with careful examination of the data from
large clinical trials.
Statins have been available since the 1980s but their risk of
inducing diabetes did not surface for nearly 20 years. When all the data
available from multiple studies was pooled in 2010 for more than 91,000
patients randomly assigned to be treated with a statin or a sugar pill
(placebo), the risk of developing diabetes with any statin was one in every 255
patients treated. But this figure is misleading since it includes weaker
statins like Pravachol and Mevacor - which were introduced earlier and do not
carry any clear-cut risk. It is only with the more potent statins - Zocor (now
known as simvastatin), Lipitor (atorvastatin) and Crestor (rosuvastatin) -
particularly at higher doses, that the risk of diabetes shows up. The cause and
effect was unequivocal because the multiple large trials of the more potent
statins had a consistent excess of diabetes.
For those statins, the higher the dose, the more diabetes, though
we don't have enough data yet to say with precision at which dose excess
diabetes showed up for each drug. What we do know is that diabetes showed up.
The numbers increase to one in 167 for
patients taking 20 milligrams of Crestor, and up to one in
125 for intensive statin
treatments involving drug strategies to markedly lower cholesterol levels.
Let's just round this off and say that one in every 200 patients treated with
any of the three most potent statins will get the side effect of diabetes.
That's quite a conservative number because diabetes was not even being
carefully looked for in most of the trials. And we have data for only 5 years
of treatment; it might be worse with longer statin therapy.
More than 20 million
Americans take statins. That would equate to 100,000 new statin-induced diabetics.
Not a good thing for the public health and certainly not good for the
individual affected with a new serious chronic illness.
If there were a major suppression of heart attacks or strokes or
deaths, that might be justified. But in patients who have never had heart
disease and are taking statins to lower their risk (so-called primary
prevention), the reduction of heart
attacks and other major events is only 2 per 100. {That number of MI
prevented depends on which study is used.
Others fail to find for moderate risk population no benefit.—jk} And we
don't know who the 2 per 100 patients are who benefit or the one per 200 who
will get diabetes! Moreover, the margin of benefit to risk is quite narrow.
What should people who are taking statins do? If they are
prescribed for someone who has already had heart disease or a stroke, the
benefit is overriding - no changes are suggested. But in the vast majority of
people who take statins - those who have never had any heart disease - there
should be a careful review of whether the statin is necessary, in light of the
risk of diabetes and the relatively small benefit that can be derived. Beyond
that, a dose reduction or use of a less potent statin should be considered on
an individual basis.
We need to find out why statins cause diabetes and, ideally,
through genomics we could determine who is at risk for this important side
effect. But to date nothing has been done to sort this out - despite the fact that the market for
statins is well over $20 billion per year. There are thousands of blood
samples sitting in company freezers around the world that could potentially
provide the answers.
The announcement, medication label change and health advisory by
the F.D.A. were long overdue, and have brought this important public health
issue to light. The information that we have does not support that this is a
"small" problem unless one considers more than 100,000 new diabetics
insignificant. The problem of statin-induced diabetes cannot be underplayed
while the country is being overdosed.
Eric J. Topol is a cardiologist at the Scripps Clinic, a
professor of genomics at the Scripps Research Institute and the author of
"The Creative Destruction of Medicine."