New Alzheimer’s Imaging Test in Use at Mount Sinai

Clinicians at The Mount Sinai Medical Center in New York are the first in the state to use a recently FDA-approved PET scanning technique using radioagent florbetapir to detect Alzheimer’s disease among cognitively impaired patients.

The patients receive an injection of florbetapir, a radioactive agent that binds to plaques in the brain, prior to the imaging procedure. Florbetapir allows the plaques to be seen in PET images. While detection of plaques is not definitive proof of Alzheimer’s disease, absence of the plaques could eliminate the disease as a possible cause for a patient’s cognitive impairment.

“Until now, a diagnosis of Alzheimer’s disease could only be pathologically confirmed at autopsy,” said Samuel Gandy, MD, professor of neurology and psychiatry, and director of the Mount Sinai Center for Cognitive Health and NFL Neurological Center at The Mount Sinai Medical Center. “Coupled with traditional clinical examination, florbetapir is a promising tool in helping confirm the diagnosis of a patient who is dealing with cognitive impairment.”

The FDA approved florbetapir, under the brand name Amyvid, in April, for the brain imaging of patients being evaluated for Alzheimer’s. Amyvid is the first FDA-approved radioactive diagnostic agent for this purpose, but there are a few other radiotracers in the pipeline. Last year, GE’s flumetamol entered Phase III clinical trials, and another radiotracer, florbetaben, is in the final stages of Phase III clinical trials, first results of which were presented earlier this year at the American Academy of Neurology’s annual meeting.

This month, data from a few florbetaben studies were presented at the SNM annual meeting and will provide the basis of the company’s FDA submission later this year, said Dr. Ludger M. Dinkelborg, CEO of Piramal Imaging. Florbetaben is a targeted radiotracer that binds specifically to these amyloid beta proteins, signaling Alzheimer’s or cognitive decline. The technique can help provide an early and definitive diagnosis.

“In several years, we won’t speak of ‘likely to be Alzheimer’s,’” Dinkelborg said in a phone interview. “We will say what type of Alzheimer’s, and this will help to give the drugs earlier and also to pick the right drugs.”

At Mount Sinai, physicians hope to use this scanning technique with florbetapir to be able to refer patients for appropriate research trials. They would also be able to monitor the effectiveness of treatments and assess disease progression, researchers said.

Josef Machac, MD, director of nuclear medicine and professor of radiology at Mount Sinai, said that approval of the procedure marks a significant advance in the evaluation of patients who show signs of cognitive impairment.

“The principal value of this procedure at this time is in excluding beta-amyloid and Alzheimer’s disease as cause for memory or cognitive decline,” he said. “This can help in patient management, and in clinical trials of investigational therapies to find more effective treatment.”

- Sara Michael contributed to this report.