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Tuesday, July 29, 2003, 12:00 a.m. Pacific
New drugs being made for specific racial groups
By Ariana Eunjung Cha
The Washington Post
OAKLAND, Calif. — Three times a day, nine patients at Dr. General Hilliard's private clinic 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 interact regularly 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 a tiny amount of the 0.1 percent genetic variation between one human and another. That means that someone who is considered black, for instance, might have more genes in common with someone who is white than someone else who is also black.
On the other hand, science also has shown that certain groups share inherited traits, and often similar ailments.
The Food and Drug Administration (FDA) gave biotech start-up NitroMed Inc. the green light to study whether its drug should be approved for use in a 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.
If the government approves the NitroMed drug, called BiDil, it would be the first time a medication has been sanctioned specifically for use in one racial or ethnic group.
Recent test results have been inconclusive. Tests of an AIDS vaccine 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 seems 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, 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 discrimination. They say racial categories are more a societal construct than a scientific one. 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 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. 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.
There have been numerous theories about why.
Do blacks suffer more because of environmental factors such as diet, living conditions or stress? 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.
Perhaps the trickiest part of race-specific clinical trials 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 Hispanic?
The NitroMed researchers 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.
"We all know we're all mixed up so much you can't really say what (we) are," said one of Hilliard's co-investigators, Charles Curry, a Howard University professor of medicine. "People self-designate at how they think they are, but that doesn't really have a biological basis."
Elyse Frazier, 56, a patient at Hilliard'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 told her she was eligible for the study.
Frazier 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 "6/16 black, 1/16 Cherokee, 1/16 Blackfoot, 4/16 white and 4/16 Mexican."
