Drug May Help Diagnose Alzheimer's Earlier
Florbetaben May Aid in Diagnosis of People With Memory Loss
Pros, Cons of Testing
Some experts question the usefulness of any test, since no drugs are available that substantially halt the course of Alzheimer's.
Sabbagh says available medications can help somewhat. But more importantly, drugs that can slow the progression of the disease are in late-stage testing. Once they become available, the tests could help doctors select patients for early treatment, when it can really help, he says.
Additionally, a diagnosis can help families in planning and in creating plans to help protect the patient, Doody says.
Another question is whether doctors can read scan results accurately and consistently. Eli Lilly has established a program to train doctors to interpret the results for its drug, Amyvid, and the manufacturers of the other agents, if approved, will presumably do the same.
There are potential pluses, too.
If the tests can help to identify people with Alzheimer's earlier, that will likely advance research, experts say. Some believe that the reason experimental drugs have failed to work up to now is because they have been tested in people whose Alzheimer's disease was too advanced.
Florbetaben and other new drugs like it have not been compared in a head-to-head study, so no one knows which works best.
But one advantage of florbetaben may be that it appears to last relatively long before it loses its radioactivity, Sabbagh says. That means it can be shipped and used at centers worldwide, while others can only be used where they are made.
Also, the researchers took the extra step of making sure florbetaben detects plaques in the areas of the brain it is supposed to -- the gray matter, he says.
The most common side effects were discomfort and bruising in the area where the drug is injected, headache, and flushing. But symptoms were short-lived, Sabbagh says.
The study was funded by maker Bayer Healthcare Berlin, which plans to submit the results with an application for FDA approval.
No cost has been established for florbetaben. Amyvid is estimated to cost $1,600 a dose, and a PET scan can run from $3,000 to $6,000. When Amyvid becomes available in June, Medicare and presumably most other insurers will not immediately cover its expense.