Two lung cancer drugs developed by Roche ($RHHBY) and AstraZeneca ($AZN), along with other related synthetic compounds, successfully reversed Alzheimer's-like memory loss in fruit fly and mouse trials. The finding comes from research that spanned the globe, involving neuroscientists in the U.S. and China.
Details of the work by Cold Spring Harbor Laboratories and others are published online in the Proceedings of the National Academy of Sciences.
The starting point here involved compounds including Roche's Tarceva (erlotinib) and AstraZeneca's Iressa (gefitinib). Both are currently approved to treat lung cancers with an overexpression of the epidermal growth factor receptor, or EGFR, by blocking the EGFR receptor. Scientists concluded from their fruit fly and mice studies that EGFR also appears connected to amyloid beta plaque buildup in Alzheimer's patients' brains and their related memory loss.
With fruit fly models of Alzheimer's disease (containing the amyloid beta-42 peptide--an Alzheimer's hallmark), they determined that EGFR activation made memory loss worse. But two anti-cancer EGFR inhibitors dosed to 3-day-old Alzheimer's-model flies prevented memory loss by day 11. Similar results grew out of Alzheimer's mouse studies. Parallel to this, researchers in the extended team determined that EGFR appears to be a viable Alzheimer's drug target. They identified three new compounds that helped restore the rodents' memory, but also prevented the amyloid beta-42 peptide from activating human EGFR in a test tube.
So much more needs to be done here. Additional animal studies must determine if the results can be repeated. Human trials are also crucial, as results in animals aren't always able to be replicated in people. What's more, researchers still are learning about Alzheimer's pathology and aren't totally sure yet about the mechanism of action and where EGFR suppression fits in. But as we've learned in recent months, plenty of Alzheimer's treatments fail by the time they reach late-stage human trials. That leaves it up to academics to come up with new approaches in preclinical trials and start the process all over again. And this concept offers enough promise that it deserves a closer, and longer, look.
- read the release
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