Race Plays
Role in New Drug Trials
Treatment by Genetic
Origin, Ethnicity Divides Medical Profession
By Ariana Eunjung Cha
Washington Post Staff Writer
Monday, July 28, 2003; Page A01
OAKLAND, Calif. -- Three times a day, nine
patients at General Hilliard's popular private clinic
here take a tiny orange pill for their heart troubles as
part of a nationwide study that some describe as the
future of drug treatment and others call medical heresy.
The diverging views stem not from what the
experimental drug contains but who is allowed to take it
-- only people who identify themselves as African
American.
The hope is to create the first prescription
medicine intended for a specific racial group. The
pursuit of such a treatment, however, has become the
subject of impassioned debate and research in the
medical community.
As more new drugs are made to attack disease based
on their genetic origins, doctors are divided over
whether race or ethnicity should play a role in
treatment decisions. And, if so, there is this practical
question: In a world of mixed heritages, how does a
doctor even determine a person's race?
"The more we learn about how drugs work the more
we see a genetic component and the race question is
among the biggest mysteries," said Hilliard, who has
been practicing cardiology for nearly three decades.
The notion of race was advanced centuries ago as a
method of social and political grouping when new
transportation methods allowed people from far-flung
parts of the world to regularly interact with each
other. The divisions often were drawn by the
superficial: skin and hair color, shape of the eye.
However, recent advances in genetic mapping have
all but dismissed race as a biological construct. Race
accounts for only a tiny amount of the 0.1 percent
genetic variation between one human and other. That
means that someone who is considered black, for
instance, might have more genes in common with someone
who is white rather than someone who is also black.
Yet, on the other hand, science also has shown
that certain groups share inherited traits, and often
similar ailments.
FDA Gives Approval for Testing
The federal Food and Drug Administration gave biotech
start-up NitroMed Inc. the green light to study whether
its drug should be approved for use in a single racial
group. NitroMed is testing its therapy at 160 sites on
what it hopes will eventually be 1,100 patients. Results
could be announced in as soon as a year.
While some doctors have for a long time adjusted
dosages or favored certain medications over others
because of a patient's race, government approval of the
NitroMed drug would be the first time a drug has been
sanctioned specifically for use in one racial or ethnic
group.
The tests come as interest grows in the medical
community over the possibility of race-based treatments.
The FDA issued guidelines this year on how racial
information should be collected in clinical trials. And
a few months ago, doctors and researchers in the New
England Journal of Medicine debated the issue in a
special section of the influential publication.
Recent drug test results have suggested some
promising but inconclusive trends: Tests of an AIDS
vaccine made by Brisbane, Calif.-based VaxGen Inc., for
instance, seemed to show that it was a failure in whites
but might have some promise in blacks and Asians. The
breast cancer drug Tamoxifen, by British pharmaceutical
giant AstraZeneca PLC, seemed to be a bit less effective
in blacks than whites.
Some experts argue that the sample sizes were too
small to draw any real conclusions and that if the
analysis was done another way no racial differences
would be found. Nevertheless, some doctors have seized
on such data to tailor their treatments by race,
switching drugs or changing dosages. They say that while
race may be an imprecise measure of people's genetic
reaction to drugs, it is the best proxy for such a
correlation available now.
"Ignoring racial and ethnic differences in medical
and biomedical research will not make them disappear,"
Esteban Gonzalez Burchard, an assistant professor at the
University of California at San Francisco, concluded in
a recent journal article he wrote with others.
Critics, though, say promoting certain drugs for
race-specific markets could lead to stereotyping and
discrimination. They say racial categories are more a
societal construct than a scientific one. Indeed, the
FDA has advised researchers to use the same race and
ethnicity groupings as the U.S. Census, categories that
resulted to a large extent from political lobbying.
"I think it's just bizarre, marketing a drug just
to people who are black. The scientific evidence
supporting the notion that there's a differential
response in race is weak or nonexistent," said Richard
A. Cooper, chairman of the preventive medicine and
epidemiology department at Loyola University in
Illinois, who has written extensively about race and
medicine.
Many scientists expect the debate to eventually
shift as more becomes known about the role genetics play
in how patients respond to drug therapies.
Scientists suspect that the frequency of certain
genes, including those for how drugs are metabolized, is
higher in certain races because of the way populations
of people settled and evolved. Tay-Sachs disease, for
example, is most commonly found in people of Jewish
descent and cystic fibrosis is common in certain
European populations. Eventually, biotech researchers
hope to design drugs that target specific genes,
eliminating the need to weigh racial or ethnic
characteristics when making therapy decisions.
Until such precision is possible, the medical
community continues to search for suitable proxies. Much
of the research on race-based medicine has focused on
heart ailments, the No. 1 cause of death of Americans.
According to numerous studies, black Americans suffer
disproportionately from cardiovascular disease -- some
say, for instance, that they may be twice as likely to
suffer heart failure and twice as likely to die from the
disease as whites.
There have been numerous theories about why.
Do blacks suffer more because of environmental
factors -- diet or living conditions? Or is it genetic?
Or are the differences a result of discriminatory
practices in medical treatment? One theory suggests that
blacks are not able to deal with salt in the same way as
whites. Today some scientists think it is possible
blacks do not suffer disproportionately from heart
disease but simply age faster than whites as a result of
the stress of dealing with racism in their everyday
lives.
Focusing on Heart Failure
NitroMed was founded in the mid-1990s when a group of
scientists formed a company to try and find a drug based
on a chemical called nitric oxide. It is found naturally
in the body and dilates the blood vessels allowing blood
to flow more easily, easing the burden on the heart.
They conducted a large study in the general
population of people suffering from heart failure, a
condition in which the heart muscle is unable to pump
blood adequately. Initially, it seemed the trial was a
failure until scientists examined the results by race
and saw something that made them catch their breaths: A
significant percentage of the 400 black patients in the
trial seemed to be living longer and better than those
not on the medication.
NitroMed postulated that perhaps heart failure in
blacks is somehow associated with how blacks produce and
metabolize nitric oxide, said NitroMed President Manuel
Worcel. Could it be that "African Americans have less
nitric oxide and destroy it faster?" he said.
That seemed to be consistent with long-standing
research suggesting that blacks do not respond well to
treatment by drugs such as beta-blockers or ACE
inhibitors, the most popular types of heart treatments.
The effectiveness of ACE inhibitors is related to the
production of nitric oxide.
Others were skeptical. They accused the company of
taking ambiguous results and seizing on them as a
marketing tactic.
Still, the results were intriguing enough that the
company decided it wanted to take a second look. It
asked the FDA whether the agency would consider
approving a drug for use in a specific racial group. In
March 2001, the FDA awarded NitroMed an "approvable"
letter, which means that the agency preliminarily
regards the medication to be safe and effective but that
certain issues need to be resolved before granting final
approval.
Robert J. Temple, associate director for medical
policy at the FDA's Center for Drug Evaluation and
Research, said approving the drug for use by blacks is
simply an extension of the agency's current practice of
including information on drug labels that note whether
any difference in the a drug's effectiveness or safety
have been found among racial groups. He acknowledged,
however, that wording the usage instructions would be
tricky.
The label would have to make it clear that "you're
not sure what's totally going on [with some racial
groups] but you'd point out benefits found in blacks,"
Temple said.
Even if the drug is approved for use only in
blacks, there is nothing to prevent doctors from
prescribing it for other racial groups if they think it
might help. Physicians often use approved drugs for
"off-label" reasons.
For now, the NitroMed study has won the political
backing from a slew of prestigious groups -- the
Association of Black Cardiologists, the National Medical
Association, members of the Congressional Black Caucus
-- and the financial support of a number of venture
capital firms including Morgan Stanley & Co., Goldman
Sachs & Co. and HealthCare Ventures.
That is how the trial of the orange pills, known
as BiDil, came to Hilliard's fourth-floor medical
offices. The NitroMed study is but one of roughly a
dozen race-specific clinical trials that Hilliard has
assisted in over the past five to six years.
The study setup is simple: Participants take BiDil
or a placebo in addition to their regular medications.
They stay on the drug for a year and a half. They are
surveyed by phone each month and are given full
in-person checkups every three months. The goal is to
compare the lifespan and quality of life of patients who
took the drug with those in the control group.
Definition Difficulties
Perhaps the trickiest part has been determining the
target patients: Who is African American? Does a recent
Nigerian immigrant qualify? What about someone who is
black but thinks of himself as Latino?
The NitroMed researchers in fact debated for
months about whether to limit the study to "African
Americans" or to "blacks" or some other designation.
They ultimately decided to go with African-Americans
because they felt it was more precise than black since
the study was not going to include many black people
from other parts of the world.
To determine who met that definition, NitroMed
allowed patients to categorize themselves, a practice
that has increasingly become the norm in medical
research but one that is not universally endorsed.
In fact, one of Hilliard's co-investigators,
Charles Curry, a Howard University professor of
medicine, is ambivalent about the trials because of the
possibility of what he calls "racial profiling."
"We all know we're all mixed up so much you can't
really say what [we] are," he said. "People
self-designate at how they think they are but that
doesn't really have a biological basis."
Elyse Frazier, 56, a patient of Hillard's clinic,
is a testament to the difficulty. When research
coordinator Jackie Rayford asked her if she might be
interested in the study for African Americans, she was
puzzled. She considered herself black in matters of
politics, but it was not a question she had ever been
asked before in a health context. Frazier's mother is
half black, half Cherokee Indian. Her father is half
black, half Blackfoot Indian.
"Do you consider yourself African American?"
Rayford asked.
Frazier answered that she did and Rayford informed
her she was eligible for the study.
Frazier, a retired nurse's assistant who suffered
a heart attack in 1980 and was recently diagnosed with
heart failure, said she enrolled in the NitroMed study
because she hopes to help future generations, including
her children and grandchildren. But, she wonders, will
all of them be eligible for the medication? Based her
calculations, one of her grandsons, she points out, is
3/8 black, 1/16 Cherokee, 1/16 Blackfoot, 1/4 white and
1/4 Mexican.
© 2003 The Washington Post Company
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