Merck turns to GE agent to track potential Alzheimer's biomarker

Three months after GE Healthcare announced upbeat results from its Phase III study of flutemetamol, which it hopes will become the state-of-the-art imaging agent for Alzheimer's disease, the company announced a key tie-up with Merck ($MRK). The pharma giant has agreed to use the diagnostic tool to select patients for its upcoming Phase II/III study of MK-8931, which it believes has the potential to grab the lead in the race among experimental drugs angling for a blockbuster market.

GE's agent is used to detect beta amyloid, a toxic protein which a host of developers--from Merck to J&J ($JNJ), Pfizer ($PFE) and Eli Lilly ($LLY)--have gambled hundreds of millions of dollars on as the prime suspect in triggering the memory-wasting ailment. GE reported that in its study of 180 terminal patients, the agent lit up beta amyloid with a median sensitivity ranging from 75% to 100% and specificity ranging from 99% to 100%. And it is in the hunt for approvals in the U.S. and Europe as a diagnostic tool.

Now a joint advisory committee will oversee its use in selecting patients for the MK-8931 study, a key test of its utility for a drug that is designed to clear plaque.

"There is a serious unmet need for a reliable method for measuring beta amyloid deposits to help physicians diagnose Alzheimer's disease at its different stages and study its progression," said Darryle Schoepp, Ph.D., senior vice president, head of neuroscience and ophthalmology, Merck Research Laboratories. "This agreement will allow us to employ an investigational imaging agent to help identify patients who might benefit from an anti-amyloid therapy and enable clinical evaluation of our lead BACE inhibitor candidate for Alzheimer's disease, MK-8931."

The approach may be logical, but the whole field has proven treacherous for developers--primarily because there's no certainty as to what causes Alzheimer's or how it can be fought. Eli Lilly gained an approval for Amyvid as an imaging agent for beta amyloid, but its presence doesn't always mean that patients have Alzheimer's. So it can only be used to rule out the disease in patients who don't have buildups of beta amyloid in the brain. Where there are accumulations, physicians are still required to consider various factors before they make a diagnosis.

- here's the press release
- read an article on Amyvid from The Philadelphia Inquirer
- here's more on the deal from FierceMedicalDevices