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PUBLIC HEALTH: Obstacle Course for the Sick
By Henry I. Miller
On drug approval, what we need from the FDA is not perfection but consistency. By Henry I. Miller.
FDA regulators need to balance patients’ access
to therapies with the safety of drugs. The consequences of poor decisions
can be grim: promote access at the expense of safety, and a dangerous
product can cause incalculable harm; overemphasize safety at the expense of
access, and patients suffer from the absence of lifesaving, life-enhancing
medications.
In recent decisions on the postapproval risk
management of two drugs, Tysabri and Rituxan, FDA regulators failed to be
internally consistent—and thereby sowed confusion among patients,
physicians, and drugmakers.
In late 2004, Tysabri became only the sixth medication
approved—and the first in several years—for the treatment of
multiple sclerosis, a common and debilitating (often heartbreaking)
autoimmune disease that affects the central nervous system. The
drug’s testing in clinical trials yielded impressive
results—the frequency of clinical relapses reduced by more than
half—and induced the FDA to grant accelerated approval.
In early 2005, however, with several thousand patients
already being treated with Tysabri, it was discovered that three had
contracted progressive multifocal leukoencephalopathy (PML), a rare and
often fatal neurological disorder caused by a virus. (Because the drug
suppresses certain components of the immune response, regulators,
clinicians, and the product’s developers had from the beginning been
sensitive to the possibility of infections as a side effect.)
Immediately—some would say prematurely—the manufacturers
voluntarily halted production and distribution and withdrew Tysabri from
the market.
An uproar ensued. Self-appointed safety watchdogs
cited Tysabri as yet another case of an allegedly harmful, inadequately
tested product finding its way to market. Conversely, MS patients and
neurologists were bitterly disappointed at being deprived of what for some
was an almost miraculous therapy—and of the ability to make their own
informed decisions about options for treatment. After the analysis of new
safety data, an FDA advisory committee recommended Tysabri’s return
to the market with revised labeling.
The exhaustive list of requirements for physicians, pharmacists, and
patients makes one wonder whether the next FDA safety innovation will
be a mandatory live-in nanny.
The FDA, however, went far beyond modifying the
labeling to contain more prominent warnings that reflected new knowledge of
the drug’s side effects (which would, in my view, have been
sufficient) and insisted instead on a baroque risk-management action plan
(RiskMAP) that imposes onerous restrictions on Tysabri. These include
limited distribution and additional education and monitoring requirements
for patients, prescribers, pharmacies, and infusion centers.
RiskMAPs were originally created by the FDA as a
fail-safe for the small number of products that offer unique benefits but
also carry atypical and significant risks. Less intrusive plans might
include special labeling and more intensive education about product use and
precautions, but the FDA adopted far more obtrusive restrictions and
requirements such as mandatory enrollment in patient registries, controlled
distribution, and prescribed behavior (such as the use of two kinds of
contraception in the case of one drug) by patients.
Other products subject to such regimes include
Accutane, used to treat severe recalcitrant nodular acne, and Thalomid, for
multiple myeloma and the cutaneous manifestations of leprosy. Like Tysabri,
both drugs provide unique and significant benefits to their users that are
not offered by other medications but have severe, rare side effects.
Accutane and Thalomid are known potent teratogens—substances capable
of interfering with the normal development of a fetus and causing birth
defects or the loss of a pregnancy or other complications—and
therefore must be avoided by women who are or who may become pregnant. But
the exhaustive (and exhausting) list of requirements for physicians,
pharmacists, and patients makes one wonder whether the next FDA safety
innovation will be a mandatory live-in nanny to monitor patients’
compliance with the RiskMAP.
The RiskMAPs for all three drugs are excessively
restrictive, seemingly more appropriate for weapons-grade plutonium than a
pharmaceutical. Although health practitioners and patients certainly need
complete and accurate information about a product’s potential risks,
regulators should enable patients and physicians to make informed decisions
within an expanding universe of therapies, not create an obstacle course
between the sick and their medications.
Self-appointed safety watchdogs cited Tysabri as yet another case of
an allegedly harmful, inadequately tested drug finding its way to market.
MS patients and neurologists were deprived of a promising therapy—
and the ability to make their own decisions.
Patients, physicians, pharmacists, and drugmakers
conform to the RiskMAPs because they have no choice; the FDA is the only
game in town, and playing along is the only way that all these stakeholders
can variously receive, prescribe, dispense, and manufacture the
medications.
And that brings us to Rituxan, a treatment for
rheumatoid arthritis and certain kinds of lymphomas. Like Tysabri, it acts
by suppressing elements of the immune system and also has been linked to
PML; there have been 23 confirmed cases of PML in patients receiving
Rituxan for the approved treatment of non-Hodgkin’s lymphoma and,
most recently, two in patients being treated experimentally for systemic
lupus erythematosus.
But, unlike Tysabri, Rituxan has never been subject to
a RiskMAP. And despite the new cases of PML in patients with
lupus—and the fact that Rituxan also is under consideration for
treatment of MS—the FDA was content merely to update the package
insert for Rituxan.
Multiple sclerosis patients on Tysabri are right to
feel discriminated against. Whereas they and their health-care providers
must navigate a veritable RiskMAP maze to obtain and maintain access to
their approved medication, patients taking Rituxan—which carries a
similar risk of PML—need not.
I am not arguing here that Rituxan should be subject
to a more restrictive RiskMAP or that Tysabri deserves a less restrictive
one (although I favor the latter), merely that the FDA’s
inconsistency sends mixed signals and creates uncertainty, the bane of
patients, physicians, and drug companies alike. Are some medications more
worthy of patient and physician discretion than others, even if they carry
the same risk? Are some patients more deserving than others of the right to
make their own decisions about risk and benefit?
Even under ideal circumstances, the regulation of
drugs involves complex risk-benefit calculations performed with incomplete
and evolving data. We cannot expect perfection from our regulators, but we
can demand sufficient consistency to make the process transparent to
patients, health practitioners, and drug developers.
This essay appeared on the TCS Daily website on March 9, 2007.
Available from the Hoover Press is To America’s
Health: A Proposal to Reform the Food and Drug Administration, by Henry I.
Miller. To order, call 800.935.2882 or visit www.hooverpress.org.
Henry I. Miller, M.S., M.D., is a research fellow at the Hoover Institution, where his research focuses on public policy toward science and technology. It encompasses a number of areas, including pharmaceutical development, the new biotechnology, models for regulatory reform, and the emergence of new viral diseases.
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