Gina Kolata
wrote in the New York Times:
http://www.nytimes.com/2013/07/10/health/rare-mutation-prompts-race-for-cholesterol-drug.html?ref=health&_r=0--about the search for a new drug that has the pharmaceutical industry all pumped up, and that indeed represents an exciting tale of medical progress.
I already
don’t like the way this post is going to sound, so I’ll start backpedalling
right off. I don’t want to sound like I am hoping that a promising new drug
possibility ends up going bust. I don’t want to sound like I am hoping that
people at risk for serious heart disease, who might be aided by this new drug,
won’t be helped. But…
The exciting
part of this story is that the promise of new therapies from mapping the human
genome has thus far not produced anything like what it was hyped, but
proponents have all along been saying, “Just wait.” And it does seem like this
story depends on recent discoveries that allow a large number of people’s
genomes to be put on the web and searched quickly with sophisticated software.
Scientists became aware of a rare gene mutation that causes a very low level of
LDL (bad) cholesterol. We know the higher your LDL, the greater your risk of
having a heart attack or stroke, and vice versa.
Three drug
companies, Amgen, Pfizer, and Sanofi, have been able to develop new drugs that
appear to mimic the effects of this gene mutation. People taking the drugs in
early tests have seen plummeting levels of LDL to points nearly
undetectable—leading to concerns that some harm might even be caused as no
physician sees such low levels in actual practice. The new drugs are not
chemical but biological agents, monoclonal antibodies that have to be
manufactured in living cells. The companies are betting on their success and
developing new factory facilities that can produce unprecedented quantities of
monoclonal antibodies.
So what could
possibly be wrong with this picture?
Kolata
fingers one fairly obvious concern. In today’s drug market, monoclonal
antibody-type drugs are hugely expensive—such as some anticancer drugs. So are
we talking about a new class of designer drugs that only the Warren Buffets of
the world will be able to afford? Presumably the drug companies are trying to
answer that concern precisely by touting the huge quantities of drug their new
facilities are planned to produce. If on the other hand they marketed any such
drug at a truly affordable price—instead of trying to milk the market for every
last buck they could squeeze—it would really be a first.
If you read
far enough into the article, another concern arises. Kolata does not mention
this case specifically, but has everyone already forgotten ezetimibe?
Readers of
this blog have not forgotten, of course, because y’all recall posts like this:
http://brodyhooked.blogspot.com/2009/11/more-bad-news-on-ezetimibe-so-why-do-we.html
Ezetimibe was
the drug contained in the brand-name products Zetia and Vytorin, and was highly
touted in its day because it had a new mechanism of action. While one way to
avoid heart disease is to have a low LDL, the other is to have a high HDL
(“good cholesterol”), which is basically the same thing as all the cholesterol
in your body is pretty much divided up into the LDL and HDL fractions.
Ezetimibe was the wonder drug of its day because it seemed uniquely able to raise
patients’ HDL, and in clinical trials, it did so quite successfully.
Only it did
nothing at all to prevent heart disease and stroke.
So the lesson
from everything we know so far about ezetimibe is that just because a new drug
has an effect on various body measurements that mimic stuff which, when it
happens naturally, is associated with lower risk of heart disease, doesn’t mean
that the drug automatically prevents heart disease. You have to do longer-range
trials to look and see whether it actually has such an effect. In the case of
ezetimibe, I suggested in this other post:
http://brodyhooked.blogspot.com/2008/01/now-that-weve-been-enhanced-whats.html--that the real take-home message might better be to have doubts about the whole theory that lowering cholesterol prevents heart disease—that statin drugs, for example, if they work to reduce the risk of a second heart attack after you’ve had a first (as they seem to), might well do so by reducing inflammation or something else, not by lowering cholesterol.
So maybe when
they test out these new monoclonal-antibody drugs, they will be shown to really
reduce the risk of heart attack, stroke, and death, and not merely to make
one’s lab numbers look pretty. And maybe then the new drugs will also prove to
be safe and not have nasty side effects. And maybe also the companies will
actually manufacture them at a reasonable cost so that regular folks can afford
them.
Maybe. But
you can see why some would not be willing to put money on it.
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