It was a good drug, an important drug, maybe the drug. It was the drug that might finally bring Alzheimer’s disease to heel.
A study of Russian subjects published in The Lancet in 2008 found that the drug, dimebon, “significantly improved the clinical course of patients with mild-to-moderate Alzheimer’s disease.”
“Dimebon shines as Alzheimer’s therapy,” Daniel J. DeNoon of WebMD wrote in July, 2008. He went on to say that the drug “is now only one clinical trial away from approval.”
Turns out, it was a rather large step away from approval. The results of that one remaining study were released last week, and the breathless headlines of the summer of 2008 have now crumbled into dust.
The Wall Street Journal, along with many others, reported last week that dimebon was no more effective than a Cinnabon. (The Journal didn’t put it exactly that way.)
The drug, the Journal said, “failed to meet its primary and secondary goals—improving thinking ability and overall daily function over six months in patients with mild-to-moderate Alzheimer’s disease,” according to the Journal’s newswire.
Robert Langreth at Forbes went further, dissecting the hype. While the media were parroting the claim that this could be the first drug to slow the course of Alzheimer’s disease, others were suspicious.
From Langreth:
The drug, a former antihistamine sold in Russia, emerged from nowhere a few years ago to become one of the hottest new Alzheimer’s drugs in testing. The excitement, however, was based virtually entirely on one smallish trial of under 200 patients conducted in Russia. And the mechanism of action of the drug was murky all along.
“This drug was so hyped,” says USC psychiatrist and Alzheimer’s expert Lon Schneider “When you look at this drug [chemically] there is nothing particularly special about it.” He says its tricyclic chemical structure is roughly similar to lots of antihistamines, antidepressants, and antipsychotic drugs. There is nothing in its structure to indicate it would have remarkable effect, he argues.
According to Langreth’s story, the drug company Medivation, which was developing the drug with Pfizer, had emphasized that dimebon had an effect on mitochondria, the energy centers inside cells. Schneider didn’t dispute that, but said the drug did other things, too, and that Medivation had pounced on the mitochondria effect and wove a story about how that made the drug a strong candidate to fight Alzheimer’s disease.
Pfizer paid a price for believing the hype; it paid $225 million two years ago for the rights to the drug. The media paid no such price, unless they gave up another shard of their credibility.
Do we hold news organizations responsible for repeating what they were told? That’s a hard call to make two years later. It would have been nice if the initial coverage had been a little more skeptical, even if reporters could not, at the time, find skeptics such as Lon Schneider to give them a different view.
But, as Sam tells Rick in Casablanca, there’s been a lotta water under the bridge since then. The more important question is: What will those same reporters and news organizations do the next time somebody claims to have the first drug to slow the course of Alzheimer’s?
A few others:
Linda A. Johnson at the AP: Pfizer Alzheimer’s disease drug fails in study. Adds the interesting angle that the drug companies plan to continue studies to see whether the drug might work if used differently.
Shari Roan on the Los Angeles Times Health Blog: Another potential Alzheimer’s medication is a bust.
Ewen Callaway on the New Scientist‘s Short Sharp Science blog (with apologies, presumably, to Michelle Shocked): Drug flop is blow to immune theory of dementia.
– Paul Raeburn
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