Lilly's Alzheimer's disaster spells trouble for entire class

Eli Lilly's latest pratfall in the Alzheimer's arena could cause plenty of sleepless nights in the burgeoning research field. As Bloomberg reports, Lilly's Alzheimer's therapy works much like a number of other therapies in the pipeline--and a disaster for one could spell big trouble for all.

For decades many researchers have operated under the assumption that the buildup of amyloid in the brain causes Alzheimer's, a memory-wasting disease that is claiming millions of new victims. But the assumption has never been proven, and with Lilly's semagacestat not only failing to treat the disease but evidently worsening its symptoms, Johnson & Johnson, Pfizer, Elan, Bristol-Myers Squibb and others could well be on the wrong track.

"We define Alzheimer's by [the presence of] plaques and tangles. There's very good evidence that the plaques play a strong role in familial Alzheimer's, and in animal models they are toxic," P. Murali Doraiswamy, a psychiatry professor at Duke, tells the Wall Street Journal's Health Blog. "But what we don't understand is the interaction between the [plaques and tangles], the timeline of events and how they interact with other things, such as inflammation and oxidative stress."

At Forbes, Robert Langreth notes researchers' concern that if Lilly's drug successfully cleared amyloid without helping patients, then everyone working on that class will likely be deeply worried. The bottom line: everyone working with the same target as Eli Lilly will now be operating under a cloud that can only be dispelled when a developer can conclusively demonstrate success against one of the biggest targets in the biotech world.

- see the story from Bloomberg
- read the WSJ report
- here's the Forbes blog