Thursday, January 17, 2008

Medicine and Race

The news that a race-specific drug for heart failure has failed and the company could go out of business raises some interesting questions about pharamceutical profits and innovation, as well as the way we think about race.

BiDil, pushed by NitroMed was a very effective combination of two old medications whose use hinged on a study that suggested that it was more effective in African Americans. Similarly, we are taught that calcium channel blockers are more effective in reducing blood pressure in African Americans.

I have always thought that the data upon which these assertions are made were rather sketchy and unconvincing (to me at least), despite the tinny ring of truth with which they were announced. "Blacks should be on calcium-channel blockers," I heard my colleagues of all races, teach the residents, and the words of a nephrologist friend rang in my other ear, "But their renal failure rate is so high, they'll have great blood-pressure control while they're on dialysis."

But he was a speaker for a drug company pushing a competing drug.

What is a poor practitioner to believe?

To suggest that one drug is better than other takes a head-to-head study, since the differences are so subtle, as to be beyond statistical verifiability between different studies with different investigators, different methods and a different patient mix. Unless there was a massive difference in survival over a couple of weeks, (i.e hard outcome, short interval, really big difference in outcome) as not to require the finesse of statistical control, it is hard to believe tis kind of assertion. Although NitroMed did a head-to-head, many other claims of one drug being better than another are based on the observation that the improvement in one study was bigger than the improvement in another.

Moreover this subtle outcome difference is predominantly associative, whose causal link must be made credible by a reasonable underlying pathophysiological process. Is there anyone in their right mind who would seek genetic differences in a specific race today? Not only is that a eugenically noxious concept, the very generalization required to make it clinically useful, is racist on the face of it.

For example, if a population is said to be more likely to respond to a given drug, or more susceptible to hypertension or more obese (or smarter, for that matter) it would behoove the practitioner to test the hypothesis with the person in front of them before drawing any conclusions. It is not the generalization that harms as much as the application of the general to the individual.

Even if African-Americans respond better as a group to this drug, it may not provide informaiton useful to a therapeutic decision.

Consider that it has been said that ACE-inhibitors are less likely to work in obese patients. The underlying pharmacology of drug distribution being affected by fat percentage, especially for lipophilic drugs, makes us think that there may be a credible scientific reason to... We may be more willing to escalate the doses or even exceed FDA recommendations, while monitoring extremely carefully for side effects, of course. After a few years, we may note that the variation in response is simply not important enough, given the cost difference and the wide choice of alternatives we have. If it doesn't work at low doses, let's just drop it and move on to other drugs.

How would a physician act differently with a hypothesis based on race, rather than weight? How is the marketing of a drug going to affect the way you ultimately try a medication, monitor for adverse effects and titrate the dose? Marketing certainly does affect the practitioner's judgment, but one must ask how? I can only see heart failure medications being initiated in a controlled hospital setting, and monitored very tightly in the outpatient. It is a situation where clinical response in the short-term is what counts, irrespective of race.

Moreover, NitroMed priced themselves out of the market and insurers and hospital P&T committees scoffed at the notion, when cheap generics exist for both components of BiDil. If the combination were so potent, the price still did not justify not taking 2 pills separately.

All I can say is this is what happens when marketing drives the drug discovery process. These are the types of drugs which have infested our armamentarium as a consequence of caving in t the profit motive of an industry in the hope of spurring innovation. All I can say is: "wrong kind of innovation."

By all means use the market, but do not blindly believe that the invisible hand is so discerning.

3 comments:

LISA EMRICH said...

Great points Z. Leads one to ask the question...was there truly a patient need to be met which wasn't being addressed with the current methods of drug delivery? If the answer is no, then what was the point in creating yet another 'me-too/combo' drug with such an expensive price tag? Other than seeing dollar $ign$ that is.

Zagreus Ammon said...

I am having trouble reconciling the impulse to regulate ("There should be a law against it") and what we have learned about the general superiority of free markets in accomplishing an improvement in living status.

There appears to be no point in what they did, but it is also the right of capital to self-destruct. Had they succeeded, would anyone be better-off? It does not strike me as a useful innovation.

Can we better regulate free markets to achieve a desired outcome, or are we stuck with old-fashioned legislated mandates?

antonio romero said...

Dr David Jones at MIT (of the Center for the Study of Diversity in Science, Technology, and Medicine) is running a conference on Race-based medicine and its implications… He wrote an op-ed at Culturekiosque.com on the subject that just ran today.

http://www.culturekiosque.com/nouveau/comment/bidil_and_race_profiling_in_targeted_medicine175.html