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Home > Scientific Objectivity > Fraud > Schizophrenia drug trials
Schizophrenia drug trials
by Shankar Vedantam - Washington Post Staff Writer
Wednesday, April 12, 2006
Why the firm funding the study gets the best results
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Pharmaceutical giant Eli Lilly and Co. recently funded five studies that
compared its antipsychotic drug Zyprexa with Risperdal, a competing drug
made by Janssen. All five showed Zyprexa was superior in treating
schizophrenia. But when Janssen sponsored its own studies comparing the two drugs, Risperdal came out ahead in three out of four. In fact, when psychiatrist John Davis analyzed every publicly available
trial funded by the pharmaceutical industry pitting five new
antipsychotic drugs against one another, nine in 10 showed that the best
drug was the one made by the company funding the study.
On the basis of these contrasting findings in head-to-head trials, it
appears that whichever company sponsors the trial produces the better
antipsychotic drug - Davis and others wrote in the American Journal of
Psychiatry
Such studies make up the bulk of the evidence that American doctors rely
on to prescribe $10 billion worth of antipsychotic medications each
year. Davis pointed out the potential biases in design and
interpretation that produced such contradictory results. Other experts
note that industry studies invariably seek to boost the image of
expensive drugs that are still under patent. Moreover, they say, the
trials are relatively brief and test drugs on patients with simpler
problems than doctors typically encounter in daily practice.
By contrast, when the federal government recently compared a broader
range of drugs in typical schizophrenia patients in a lengthy trial, two
medications that stood out were cheaper drugs not under patent. The
medication that worked best for patients with severe, intractable
schizophrenia was clozapine, whose sales lag well behind every other
drug in its class. And an earlier leg of the study found that the
largely unused drug perphenazine had about the same risks and benefits
as far more expensive competitors that are widely assumed to be safer.
Reliance on industry-sponsored studies is not limited to psychiatry, but
experts say the problem is exacerbated in areas of medicine where the
goal of trials is not to demonstrate cures but to measure symptomatic
relief, which allows more latitude in how the results are interpreted
and marketed. Now a growing chorus of experts is asking whether the
research establishment needs to be reoriented toward publicly funded
studies that might better guide clinical decisions and the billions of
tax dollars the government itself spends on treatment.
A perfectly independent agency has to be set up that says, "Here are
the areas where trials must be done," said Drummond Rennie, deputy
editor of the Journal of the American Medical Association. "There will
be two classes of trials -- the believable ones and the non-believable
ones".
The problem is not that companies fabricate results, experts say.
Researchers, in fact, want drugmakers to sponsor more studies, not
fewer. But ostensibly valid industry studies can be misleading in
multiple ways, Davis said. Some use too low a dose of a competitor's
drug, while others choose statistical techniques that show their drug in
the best light. Virtually all test drugs on patients with relatively
straightforward problems.
Davis warned that the circular results he found could undermine the
confidence of clinicians and patients, and even cast doubt on
medications that are genuinely superior. He and Rennie also questioned
academic researchers' role in these studies.
Davis, who joked in an interview that he no longer gets to fly first
class to Tokyo and Monte Carlo since he stopped accepting money from
pharmaceutical companies, guessed that 90 percent of industry-sponsored
studies that boast a prominent academic as the lead author are conducted
by a company that later enlists a university researcher as the "author."
"We know that happens all the time," Rennie said. "The only reason that
the company wants a non-company person as an author is to give credence
to an advertisement. . . . The whole entire paper from start to finish
is an advertisement. It is a much more subtle and telling ad than
anything they can publish as an ad."
Drugmakers defend their studies, and Davis emphasized that the drugs do
help patients. But doctors, he said, cannot afford to take the results
at face value.
Sara Corya, medical director for neuroscience at Eli Lilly, a company
Davis singled out for praise for the quality of its studies, said that
conflicting results do not cancel each other out, and that they help
clinicians understand the strengths of different drugs. Corya and Davis
noted that Lilly has strict rules to prevent author-shopping.
"The reality is that even in head-to-head comparisons, study results
will differ for a variety of reasons, some transparent, some opaque,"
added Mariann Caprino, a spokeswoman for Pfizer, whose antipsychotic
drug Geodon did not perform as well as Zyprexa in two trials funded by
Eli Lilly. Pfizer's own studies found that Geodon was superior to
Zyprexa in one trial and inferior in another.
"What this all means," Caprino said, "is there is no substitute for the
judgment and experience of the clinician in selecting among a
fortunately broad palette of medicines."
But several experts say industry-sponsored trials are failing to answer
the questions doctors really need answered: Which drug works best for
which patient? Are differences in drugs worth the differences in cost?
How many patients are likely to recover entirely, rather than just show
progress in the right direction? Head-to-head trials of similar
medications may show statistical differences in how they perform, but
those differences may not mean very much for doctors and patients, said
Robert Rosenheck, a Yale psychiatrist.
What a clinician wants to know is whether the patient she is treating
will get better on a drug, said Thomas R. Insel, director of the
National Institute of Mental Health. "If they are not going to get well,
what is the better approach? The public is less interested in
statistical significance and more interested in clinical significance."
The difference between the two was highlighted by the recent study of
antipsychotic drugs funded by the National Institute of Mental Health.
Rather than focus on how some symptom or side effect waxes and wanes,
the government trial focused on the big picture: How do typical
schizophrenia patients fare on the drugs over the long term?
The results were sobering: Regardless of the drug, three-quarters of all
patients stopped taking it, either because it did not make them better
or had intolerable side effects. The discontinuation rates remained high
when they were switched to a new drug, but patients stayed on clozapine
about 11 months, compared with only three months for Seroquel, Risperdal
or Zyprexa, which are far more heavily marketed -- and dominate sales.
"Clozapine is better by far than the other antipsychotics," said Carol
Tamminga, a psychiatry professor at the University of Texas Southwestern
Medical Center at Dallas, who wrote an editorial in the American Journal
of Psychiatry about the trial. "The question is: Why do doctors not use
it?"
The drug requires more careful monitoring to prevent potentially fatal
bone-marrow toxicity, she said, but a national monitoring program
ensures it is used properly. Tamminga agreed that marketing may play a
role in why the drug is not used more often.
"Clozapine is less marketed," she said. "It is off patent. Even when it
was on patent, it has never been as actively marketed as the other
drugs."
The government study also provided the big picture missing from
company-sponsored trials, said Jeffrey Lieberman, a Columbia University
psychiatrist who led the first phase of the study: "The drugs work, but
only so well. They are not meeting expectations."
By focusing on the horse race -- which drug is marginally better --
industry studies obscure the reality that better drugs are needed
overall, agreed Rennie, who is a professor of medicine at the University
of California at San Francisco.
"Finding the 100th similar antipsychotic drug is not where the research
should be," he said. "It should be to develop new drugs, not 'me, too'
drugs."
Rennie said that government agencies such as the Centers for Medicaid
and Medicare Services and the Department of Veterans Affairs that
disburse billions of dollars for treatment should rely on publicly
funded studies.
"There are lots of questions that drug companies are not going to be
primarily interested in," agreed Robert Temple, a senior official at the
Food and Drug Administration. He has long been a personal advocate of
what he calls a "national problems laboratory."
But Uwe Reinhardt, a political economist at Princeton, said drug
companies, device manufacturers and even physicians are reluctant to
delve into questions of cost-effectiveness because such inquiries may
find that the latest, most expensive treatment is not worth the cost.
"I have come to believe a lot of inefficiency is quite deliberate and
supported by Congress," he said. "One person's inefficiency is another
person's income."
This article originally appeared on the website of The Washington Post
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