The Food and Drug Administration (FDA) has approved Amyvid (florbetapir F18 injection), Avid Pharmaceuticals/Eli Lilly and Company's positron emission tomography (PET) tracer, for A-Beta plaque imaging in cognitively impaired patients being clinically evaluated for Alzheimer's disease. The compound will be available for use in June, with the aim of helping researchers rule out - not diagnose - the disease.
"Amyvid is the first and only FDA-approved radioactive diagnostic agent for brain imaging of amyloid plaques in patients," said Daniel Skovronsky of Avid in a telephone press briefing today. Approval "offers physicians a tool that, in conjunction with other diagnostic evaluation, can provide information to help physicians evaluate their patients."
Amyvid's main purpose will be to rule out AD; a negative scan means little or no plaque is present, which effectively rules out AD as the cause of the person's cognitive decline. This could help the approximately one in five patients who are diagnosed with Alzheimer's but later at autopsy show no evidence of the disease. "A physician can further evaluate [a patient] to try and figure out what they really have," Skovronsky told Alzforum. However, since plaques can be present in both people with or without AD, a positive scan - indicative of moderate to frequent plaques - would not establish an Alzheimer's diagnosis. Further, Amyvid is not approved to monitor plaque response to therapies or predict risk for dementia, Skovronsky said.
An FDA advisory panel temporarily rejected Avid Pharmaceutical's new drug application in January of 2011, pending better inter-reader reliability of the scans.