A new drug for heart disease, which its manufacturers say is particularly effective in African-American people, has sparked a debate on genetics, medicine and 'race'. Researchers at the University of Minnesota halted a clinical trial for BiDil, because the evidence for the drug's effectiveness was 'so compelling' that the scientists felt it was unethical to withhold the drug from the participants being given a placebo. Since all of those taking part in the trial were black, BiDil is now set to become the first 'ethnic medicine' to be licensed by the US Food and Drug Administration (FDA). However, critics say that there is no evidence that the drug is more effective in particular ethnic groups: they believe the claims are misleading and could reinforce myths about 'racial differences'.
The results of the trial, which involved more than 1000 black patients, are due to be unveiled on 8 November. Bidil is actually two existing drugs, isosorbide dinitrate and hydralazine, combined in a single pill. Lead researcher Jay Cohn says that the clinical trial only included black people because earlier studies suggested they were more likely to respond than other patients. But Jonathan Kahn, a US law professor, says that despite its success, the trial doesn't justify attempts to promote BiDil as an African-American drug. 'The trial says nothing about whether it works better in blacks because no one else was tested', he said.
Kahn believes that current attempts to sell BiDil are a marketing ploy by manufacturers NitroMed, following the FDA's earlier rejection of the drug. But, he and others claim, packaging medicines in this way could mislead patients and reinforce myths about racial differences. However, others say that examining racial differences in disease is vital to addressing inequalities in healthcare. At a conference in London last week, UK scientist David Goldstein said that while some medicines do work differently in different ethnic groups, there was a danger of oversimplifying the situation. He warned that 'we need to dig deeper to find out what causes these differences and then test for the genes involved, not market drugs on the basis of race'.
Pharmacogenetics, the matching of medicines to a person's genetic make-up, is based on the knowledge that people react to drugs differently, partly because of underlying genetic variation. However, most geneticists reject the concept of 'race' as biologically meaningless. Although certain ancestral human populations may share particular characteristics, including reactions to medicines, skin colour is not a reliable indication of ancestry. An editorial in the October issue of the journal Nature Genetics argues that traditional categories of race based on skin colour are misleading when trying to uncover genetic and environmental influences on health.
