The FDA Proposes a New Guidance About
Distributing Scientific and
Medical Publications on Unapproved New Uses:
It Doesn't Address the Problem of Publication Bias
On
Friday, February 28th, the FDA made
available a new
proposed Guidance on the subject of pharmaceutical companies'
distribution of
published
materials that
report on studies
of their drugs for "unapproved" uses.1
The marketing of pharmaceuticals is a huge enterprise. According to
a study by the Pew Charitable Trusts Health Initiative,
pharmaceutical companies spent $29 billion in 2012 to promote the use
of their drugs, with $15 billion of that spent on direct marketing to
doctors by pharmaceutical reps, a practice known as "detailing."
For some drugs, a major portion of the promotion
effort is aimed at generating
"off-label" use, which is the
prescription of
a drug
for diseases or conditions for which the FDA has not received
sufficient evidence to determine
the drug's safety and efficacy. Until
the mid-nineties, the FDA took a hard and fast position limiting the
ability of pharmaceutical companies to promote off-label use of their
drugs. The
FDA's position was straightforward: placing a drug on the market for
a use which has not been approved by the FDA is selling the drug
without adequate information about its safety and efficacy for that
use, which renders the drug "misbranded" in FDA parlance
and the marketing illegal. If
a drug maker wanted to promote a new use of an already approved drug,
then the FDA's view was that the only proper way to do so was to do
studies that were reviewed by the FDA and sufficient to support
adding that use to the drug's label. Then,
in a series of decisions, the District of Columbia Court of Appeals
ruled that drug
makers'
dissemination of information about unapproved uses was
commercial speech and
merited protection under the First Amendment.
That view was partly adopted by statue with the Food
and Drug Administration Modernization Act of 1997.
Since then, the FDA's efforts have been directed at defining the
appropriate limits on off-label promotion, consistent with the First
Amendment.
Doctors
are free to prescribe any drug for any condition, with only their
professional judgment (and sometimes the patient's insurance
coverage) as a constraint. If
a doctor wants to prescribe a drug that has only been approved for
the treatment of major depression for a patient that has obsessive
compulsive disorder, then the doctor is free to do so. Of course,
the doctor is more likely to do so if a pharmaceutical sales
representative has provided the doctor with a copy of a published
study that concluded the drug was in fact useful for the treatment of
OCD. Journal
articles of
this general type represent
by far the biggest source of concern, and the FDA's attempt to ensure
that pharmaceutical
companies' dissemination
of such journal
articles does not mislead doctors and patients is front and center in
the proposed Guidance. Why
would the distribution of reprints of published articles be
misleading, or worse, potentially dangerous? For several reasons.
For one, such studies are often too small to allow any firm
conclusion about the relative risks and benefits of the drug in a new
use, or reach
conclusions based on measurements of an endpoint that
is only suggestive of real benefit.
This can be the case even with FDA approved indications, as the
recent example of Avastin's use in breast cancer illustrates. The
FDA approved the use of Avastin in metastatic, HER-2 negative, breast
cancer based on studies that demonstrated that Avastin's use resulted
in a significant increase in progression-free survival (the length of
time after treatment during which the disease does not get worse).
However, further studies demonstrated that despite the
progression-free survival, the patients over-all survival, which is
the time from treatment until death, did not change.
Avastin, a costly drug which has its own adverse effects, did not
help breast cancer patients live longer, and that use was removed
from the label. Because the FDA approved the use on the basis of the
more preliminary finding, the maker of Avastin was required to do the
further study that showed no ultimate benefit. Of course for studies
of uses that are and remain off-label, there is no such requirement,
and off-label uses that are stimulated by preliminary findings would
likely continue in the absence of the follow-up definitive studies.
An
even bigger pitfall for the dissemination of materials concerning
off-label use is publication bias. The
FDA's proposed Guidance deals with the problem of handing out
reprints of publications by focusing on fundamental elements of
reasonable science and fairness, such as the character of the journal
(peer-reviewed by independent experts), the balance of the material
distributed (not inconsistent with the weight of the evidence from
all published
studies on the
issue, the absence of conflict of interest, and so on. All this
certainly is necessary, but it is hardly sufficient. The problem
goes beyond ensuring reasonable peer-review
and disclosure of financial conflicts, to the heart of the very
publication process, which is
rife with
publication bias,
and the often-flawed
data analysis and reporting in
studies that are published.
Vedula et al. published a stunning analysis,
in the New
England Journal of Medicine, of
the publication bias and outcome reporting bias in the case of
off-label studies for the drug gabapentin.2
My colleague, Joanna Sax, examined the problem of publication bias
and deception in drug promotion at length in her article Protecting
Scientific Integrity: The Commercial Speech Doctrine Applied to
Industry Publications3
and,
in addition to documenting and detailing the scope of the problem,
suggested that the problem be considered one of deceptive marketing
and proposed a statutory fix. In the case of the FDA's proposed
Guidance, a statute is not needed. A reprint that reports positive
results in a study of the off-label use of a drug is misleading not
merely if other published studies report negative results, but is
just as misleading if unpublished
studies
reached negative conclusions. The FDA needs to require
pharmaceutical companies to disclose and distribute the results of
any negative unpublished studies, in reasonable summary form, if they
wish to disclose and distribute positive published studies of the
same drug for the same general indication.
1
FDA, Revised Draft Guidance for Industry on Distributing
Scientific and Medical Publications on Unapproved New
Uses--Recommended Practices; Availability, [Docket
No. FDA-2008-D-0053] (February 28, 2014).
2.
S. Swaroop
Vedulla, Outcome
Reporting in Industry-Sponsored Trials of Gabapentin for Off-Label
Use,
N.
Engl.
J.
Med.
2009;
v. 361:1963-71
(Nov. 12, 2009).
3Joanna
Sax, J.D., Ph.D.,
Protecting
Scientific Integrity: The Commercial Speech Doctrine Applied to
Industry Publications,
37 American
Journal of Law & Medicine
203 (2011)
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