On June 23, 2005, American medicine managed to take a small step forward and a giant step backward at precisely the same time, with government approval of the first medication to be earmarked for a specific racial group. It was BiDil, a drug designed to treat heart failure in blacks.
Enthusiasts hailed BiDil's approval by the Food and Drug Administration as a landmark event in the nascent field of pharmacogenomics, which aims to create drugs tailored to fit an individual's genetic makeup as precisely as a bespoke suit drapes its owner's shoulders. Critics just winced and clocked one more misstep in medicine's long history of race-related disasters.
You would think that the elucidation of the human genome would have cleared up most of the hoary untruths surrounding race and health. But as Jonathan Kahn makes clear in his worthy if convoluted review of the events surrounding the birth of BiDil, the genome has in many respects only made things worse.
It has been clear for decades that race has minimal relevance to the body's inner workings. Research has repeatedly shown that the biologic variations among individuals of the same race are reliably great enough for race to retain little utility as a biologic predictor. You might as well sort people by height. Or, in the words of an editorial writer for Nature Biotechnology in 2005, "Pooling people in race silos is akin to zoologists grouping raccoons, tigers and okapis on the basis that they are all stripy."
But old misconceptions die hard, particularly for entrepreneurs eagerly awaiting cash bonanzas from the genomic revolution.
Race may be irrelevant; it may be, as Dr. Francis Collins, the director of the National Institutes of Health, put it, "a weak and imperfect proxy" for genetic differences. But it is also a familiar concept — and asking people what race they are is substantially cheaper than genotyping them.
So in a peculiar paradox, race has come to serve in some circles as a crude surrogate for genetic analysis until actual genomic medicine comes along — a temporary bridge from now to later, known to be flawed but still a quasi-legitimate stand-in for the real thing.
Against this background unfolds the story of BiDil, a drama of greed and good intentions.
Several observations prompted the drug's development. Among them was the common assertion from the last century that blacks with heart failure were more likely to die than whites. (Mr. Kahn does an impressive job of researching and debunking this statistic.) Then there was the belief that blacks often reacted badly to some of the newer drugs used for treating heart failure, and the results of a study dating from the 1980s suggesting that many black patients did well with two old standby drugs.
Those two drugs were (and are) on sale as generics, costing pennies a pill. But just suppose they were combined into a single pill that could be then specifically marketed to patients who just happened to be thought in particular need of effective medication? Now there was a pharmacologic and marketing plan that would extend a lucrative new patent for decades.
And so it came to pass that a collection of eager investors and some of the nation's foremost cardiologists smiled on the results of an industry-sponsored trial performed on self-identified black subjects with heart failure: The two cheap drugs combined into the not-so-cheap BiDil reduced mortality by 40 percent compared with placebo. This figure was impressive enough to end the trial early and speed BiDil to market.
How did whites do on BiDil? Nobody bothered to check.
Mr. Kahn deserves credit for teasing out all the daunting complexities behind these events, including the details of genetic analysis, the perils of racial determinations and the minutiae of patent law. Unfortunately, though, he suffocates his powerful subject in a dry, repetitive, ponderous read.
A law professor with a doctorate in history and longstanding interest in race issues, Mr. Kahn trudges a partisan path through the drama in which he himself was a player. (He testified before an F.D.A. advisory committee that BiDil should be approved without racial qualifications.)
He heads bravely into many statistical thickets, but omits relevant clinical data; he repeatedly refers to the trial that led to BiDil's approval, for instance, but I could find its numerical findings nowhere in the book and had to look them up. In a story that fairly drips with potential human interest, he offers the reader not one sip.
The issues raised on every page are so important and so thought-provoking that it would be irresponsible to warn interested readers away. Still, it would be almost as irresponsible to misrepresent the difficulty of the journey.
As it happens, BiDil itself has had a remarkably inglorious career. Despite its much-trumpeted release, patients did not request the medication, and practicing doctors did not prescribe it.
NitroMed, the company that developed it, sponsored no further studies and failed in 2009.
The drug still lingers on the market; Mr. Kahn writes that BiDil may be resurrected in sustained-release form — that other time-honored technique for wringing a few more years from a drug's patent.
For a parable of early 21st-century medicine, as it treads water between past and future and never hesitates to reach for a buck, it doesn't get much better than BiDil.
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