A promising new imaging agent could mean a giant leap forward in diagnosing Alzheimer’s disease.

In early February, the Ronald Reagan Presidential Foundation & Library hosted a special celebration of the late president’s 100th birthday. There were speeches, musical performances, a 21-gun salute, and plentiful media coverage. Whatever you think of Reagan’s past politics, many would agree that for the 8 years he served in office, he helped restore a troubled America through his own inimitable way of restoring hope.

It seems fitting then that as many across the country celebrated this iconic figure of hope, the molecular imaging community announced some of the most significant and hopeful news we have ever had about Alzheimer’s disease.

In late January, an advisory committee to the Food and Drug Administration unanimously recommended the approval of the first imaging test that can show the characteristic plaques of Alzheimer’s disease in the brain of a living person. Specifically, the committee called for the approval of a new imaging agent, florbetapir, which is used in conjunction with PET scans to detect beta amyloid plaques of the brain that may cause Alzheimer’s.

Ronald Reagan was among the first to “put a face” on Alzheimer’s disease. Though he died in 2004, he battled with the disease for at least 10 years, perhaps even longer—before it was diagnosed. In 1994, the general public knew very little about Alzheimer’s. But when the former president was diagnosed, suddenly the spotlight was on this debilitating disease. The prominent actor turned politician did for Alzheimer’s what Michael J. Fox did for Parkinson’s disease. He made a harrowing—but previously hidden—neurological ailment a visible and stark reality for all. Suddenly, the average American began to recognize the terrifying symptoms in a spouse, a grandparent, or even in oneself.

Today, more than 5 million Americans suffer from Alzheimer’s disease. If the FDA ultimately approves the PET scans with florbetapir, the result will be a major leap toward the accurate diagnosis of the disease. Presently, clinicians diagnose Alzheimer’s through a ruling out process. “For many years, the in vivo diagnosis of Alzheimer’s disease has been a process of exclusion of other disorders that may affect cognition,” said Karl Herholz, MD, president of the Society of Nuclear Medicine’s Brain Imaging Council. “Now, for the first time, PET scans utilizing florbetapir will provide disease-specific inclusion criteria in the in vivo diagnosis of the disease.”

Plaques are part of the criteria for having Alzheimer’s. But right now, the only way to know if the plaques are present is to do an autopsy. According to a report in The New York Times (January 20, 2011), the new agent combined with a PET scan”…would be especially valuable in a common and troubling situation—trying to make a diagnosis when it is not clear whether a patient’s memory problems are a result of Alzheimer’s disease or something else. If a scan shows no plaque, the problems are not caused by Alzheimer’s and could be from tiny strokes or other diseases.”

If the imaging agent, produced by Eli Lilly and Company under the name Amyvid, receives FDA approval, it will be a win for millions of future patients. And it will surely be a win for the Gipper.

Marianne Matthews

Marianne Matthews