The
US Food and Drug Administration is under intense pressure
to shore up public confidence in the safety and quality of
prescription drugs. Drug experts are scrutinizing the risks
associated with long-term use of statins, following the withdrawal
and labeling changes for COX-2 inhibitors. Reports of a rare
blindness among users of Pfizer's impotence drug Viagra have
raised alarms. Members of Congress and health professionals
are proposing strategies to accelerate FDA2s disclosure of
serious adverse event information, to compel manufacturers
to make proposed label changes, and to complete promised post-marketing
studies.
FDA is responding with a range of programs and policies designed
to make drug safety information available to the public, including
proactive programs for identifying safety signals related
to marketed drugs. Pharmaceutical manufacturers are facing
the increased need for public disclosure of product quality
concerns, added pressure to complete Phase IV studies, changes
in drug distribution practices, and fines or product recalls
for companies that fail to comply--more intense monitoring
for counterfeit or adulterated products is an added plus.
Call for transparency
Health and Human Services (HHS) Secretary Mike Leavitt announced
several FDA drug safety initiatives this past February designed
to demonstrate the agency's ability to address drug safety
concerns. Since then, FDA has been issuing guidances and developing
programs to implement these proposals. The agency recently
named the members of its new Drug Safety Oversight Board,
which was formed to assess particular safety issues related
to marketed drugs. The board also will provide an internal
forum for resolving disagreements among FDA staffers over
the management of drug safety issues. The board includes key
officials from FDA and other HHS agencies, but remains in
the Center for Drug Evaluation and Research (CDER), as opposed
to being more independent as some reformers proposed.
One early task for the safety board is to determine criteria
for posting drug safety information about FDA's new Drug Watch
Web site. This online information service was established
to inform the medical community about emerging drug safety
problems, including those involving off-label medication uses.
Manufacturers are watching closely to ensure that Drug Watch
safety alerts are determined by accurate and unbiased information.
But, they are concerned that manufacturers will have no opportunity
to assess the validity of safety information before FDA discloses
it online.
FDA also has commissioned the Institute of Medicine (IOM)
to conduct an independent assessment of its current system
for evaluating post-marketing drug safety and to recommend
ways to improve its surveillance and assessment practices.
The IOM panel held an organizational meeting in June and will
begin its serious work at a second meeting on July 25, 2005
to complete its report before July 2006. The committee will
examine how FDA fits into the nation's broader system for
ensuring drug safety, current FDA and industry efforts to
evaluate and manage safety problems, and whether FDA needs
additional legal authority or organizational changes to deal
with post-marketing safety issues more effectively.
HHS officials hope that these efforts will head off moves
on Capitol Hill to enact legislation establishing a new drug
safety office that is much more distinct from existing FDA
drug approval activities. Sens. Charles Grassley (R-Iowa)
and Chris Dodd (D-Conn) introduced a bill in April that seeks
more autonomy for FDA staffers involved with post-market safety
assessment so that they will feel free to sound warnings about
medications raising safety concerns. The bill establishes
an FDA post-market drug evaluation center separate from CDER
that would determine the need for label changes or possible
market withdrawal of drugs found to carry high risks. The
legislation also levies fines on companies that fail to complete
postmarketing study commitments and gives FDA the authority
to require label changes on marketed drugs.
Backers of this and other similar legislative proposals believe
that Congress should act now because FDA's new drug review
board is not sufficiently independent, and the IOM will take
a year to complete its evaluation. At the April meeting of
FDA's science board, members urged FDA to lay out the critical
elements of an ideal post-market surveillance system for drugs
and for biologics and medical devices. Such an analysis would
permit this board of experts to recommend changes to the IOM
panel, to Congress, and to other safety advocates. These issues
also are being explored by FDA's Drug Safety and Risk Management
Advisory Committee, which offered recommendations for strengthening
the agency's adverse drug event reporting system at its May
meeting and plans to hold further sessions about FDA's methods
for detecting and assessing drug safety problems.
Seeking safety data
FDA now relies primarily on its spontaneous adverse event
reporting system (AERS), which receives AE reports from manufacturers,
and from health professionals and patients through the MedWatch
program. This system works fairly well in catching signs of
serious problems related to the short-term use of drugs for
acute illnesses. It has the advantage of covering all drugs
marketed in the United States, being relatively simple to
operate, and being able to detect AEs that do not appear in
premarket clinical trials.
The main shortcoming of AERS is that it relies on third parties
to submit AE reports, which may be slow and often yields incomplete
or irrelevant information. Even though AE reporting has been
rising (more than 400,000 reports are filed with FDA each
year) the system captures only approximately 10% of serious
events, which barely scratches the surface of drug related
safety problems. The vast majority of these reports come from
manufacturers that are required to inform FDA quickly of serious
problems and to file periodic reports about all adverse event
information.
Spontaneous reports also are unreliable because reporting
rates vary a great deal for numerous products. In addition,
the volume may be affected by media coverage of a drug safety
case or problems arising within a drug class. Moreover, the
system does a poor job of assessing events with a lot of background
noise such as heart attacks that are commonly experienced
by patients taking blood pressure medication. And, many of
the reports received by AERS are duplicative; a physician
or pharmacist may submit a report directly to MedWatch and
also to the manufacturer, which in turn includes it in its
report to FDA.
Checking drug quality
Interestingly, some AERS reports involve a lack of drug efficacy
that arises from manufacturing quality issues, product adulteration,
or counterfeiting. CDER's Office of Drug Safety (ODS) reviews
and transmits such quality-related AE reports to CDER's Office
of Compliance, which oversees drug quality reporting and ensures
manufacturers submit timely and accurate AE reports. OC's
Division of Compliance Risk Management and Surveillance manages
the Drug Quality Reporting System (DQRS), which receives some
3000 adverse reports a year, nearly 12% of the AERS total.
Most of these reports involve packaging and labeling problems,
product contamination, or visual change. These come primarily
from pharmacists who notice crumbling, discolored pills, and
other product defects. DQRS staff assesses whether adverse
event reports related to product defects raise significant
health hazards or problems with good manufacturing practices,
which may lead to recalls or label-packaging revisions.
OC's risk management division also monitors the quality of
marketed drugs through targeted product sampling and monitoring
manufacturers' field alert reports that identify serious safety
problems. The staff uses this drug quality information to
identify industry trends associated with pharmaceutical manufacturing,
packaging, and labeling. One aim of this operation is to identify
those firms that produce drugs associated with more serious
health risks to consumers. These firms may be targeted for
more frequent plant inspections or closer FDA surveillance.
Manufacturers that fail to comply with reporting requirements
or to address quality problems may be referred to FDA's Office
of Regulatory Affairs.
FDA also may learn of safety problems related to product
labeling and packaging through reports of medication errors
from several sources, including a hospital error system managed
by the US Pharmacopeia. ODS's Division of Medication Errors
and Technical Support evaluates the cause of such errors,
which often may involve inappropriate dispensing in a pharmacy
or mistakes in the patient care environment. If the medication
error arises from confusion in product name, label, or packaging,
FDA deals with it directly.
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