Monday, July 11, 2005

More BiDil News

BiDil, the anti-heart-failure drug marketed toward African-Americans, has recently been approved by the FDA. This opens up a whole can of worms on the genetics of race with debates lingering at the intersection of sociology, pharmaceuticals, and evolutionary genetics. What is race? What are the important differences between races? Is it fair to offer certain drugs only to specific racial groups? Is race (as it's defined in the sociological context) even a biologically meaningful classification?

Nature Genetics just published a letter to the editor from Jonathan Kahn, a faculty member at the Hamline University School of Law. Dr. Kahn is an expert in the law of biotechnology, and he makes a few important points which I quote below.

"The FDA approval of BiDil for only African Americans would give the federal government's stamp of approval to using race, in effect, as a genetic category. But race is not genetic, as even the BiDil researchers admit. Once we sanction such talk, it is a short step to talking about races as inferior and superior. Given our nation's troubled history of racial oppression, this should not be taken lightly.

"In fact, the data from the clinical trial of BiDil (called A-HeFT, for African American Heart Failure Trial) says nothing about whether BiDil works differently or better in African Americans than anyone else. This is because A-HeFT enrolled only "self-identified" African Americans; there was no comparison population.

"Why then did NitroMed, the corporate sponsor of the A-HeFT trials and holder to the rights to BiDil, seek race-specific approval for its drug? Perhaps the answer lies not in medicine but in commerce. NitroMed holds a patent for a non-race-specific use of BiDil, which expires in 2007; it also holds a race-specific patent that lasts until 2020. This extra 13 years of patent protection may present a compelling commercial reason for seeking to cast BiDil as a racial drug, even though to do so is not supported by the medical evidence."

The case for this being an opportunity to extend a patent seems circumstantial, but Kahn does make an important point regarding the non-comparative nature of the testing. Shouldn't the drug be shown to perform statistically better in African-Americans than non-African-Americans before it's marketed specifically to one group? I'd think so.

Kahn also spends a bit of time discussing the general topic of race-specific medications, questioning whether racial differences in response to drugs are genetically based. He takes issue with many of the racially targeted treatments on the grounds that there is not any good evidence yet that racially designed treatments target genetic differences important to the disease.

The main concern, however, is the reification of race as genetic. While there are genetic components to what we consider race, we still aren't sure what the genetic differences between racial groups mean. There is an enormous amount of genetic diversity within African populations (more than the rest of the world combined), but there are also many genetically unique African populations. I would expect that the variance in response to a treatment would be much greater among Africans (and people of African ancestry) than among any other racial group. If this is the case, BiDil may only work on a specific subset of African-Americans and not the entire population.


At 12:48 PM, Anonymous Anonymous said...

Is race (as it's defined in the sociological context) even a biologically meaningful classification? ... But race is not genetic

Well, of course, race is genetic. I actually get kind of tired of PC scientists claiming that it isn't genetic. There was an issue of Scientific American about a year ago where biologists discovered certain genetic areas where race could easily be distinguished. Yes, of course, race is genetic. People should stop trying to combat racism by claiming that race is purely a social construct, and, instead, admit the obvious: race is genetic, some races are more poorly suited to dealing with certain diseases, but there are no important differences in capability between people of different races.

At 4:19 PM, Blogger RPM said...

Certain alleles are associated with different populations (races). Check out what an anthropologist (John Hawks) says about it:

The debate is not over whether or not we can apply association tests (eg, those available in Structure) and retrieve our sociologically defined races (we can). The question is whether those populations are biologically differentiated in any meaningful way (other than skin tone or facial characters).

Also, it is important to understand the genetic structure of human populations. For example, African is not even a genetically meaningful group as it is made up of many distinct populations, some of which are more closely related to European populations than to other African groups. Africans are paraphyletic and so diverse that saying there is an "African" race shows ignorance of both the biological meaning of race and the natural history of African populations.

Furthermore, African Americans are an admixed group made up of primarily West African ancestry, but also European, Native American, and Carribean (among others). This (along with the genetic diversity of African populations) poses problems in race based treatment plans.

At 4:30 PM, Anonymous Anonymous said...

Er, in response to the first commenter. Genetic racial tags are not immediately apparent That is why it is so controversial. With that claim a cite to the SA would be nice. And slapping the labile PC on something is poor arguing.


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