Eli Lilly has received an FDA Warning Letter because of a “misleading” image of a multicolored brain scan that appeared on the company’s website for the diagnostic Positron Emission Tomography (PET) tracer, Amyvid. Amyvid is indicated for PET brain scans to review β-amyloid neuritic plaque density in patients who are being evaluated for Alzheimer’s Disease.

According to FDA, the use of the colored brain image classifies as misbranding because Amyvid’s product labeling states that Amyvid images must be displayed and reviewed in black and white. Black and white scale “with the maximum intensity of the scales set to the maximum intensity of all the brain pixels” is necessary for accurately reviewing the scans. Amyvid’s product information also includes several black and white example scans to illustrate interpretation. The use of a color image suggests that the scans can be displayed and interpreted in color.

“While many PET images are displayed and reviewed in color, Amyvid scans...must be displayed and reviewed using a black and white scale,” states FDA’s Warning Letter. “Additionally, the [product insert] does not provide instructions for estimating β-amyloid neuritic plaque density using a color scale with Amyvid. Therefore, use of color PET scan image of a brain in Amyvid promotional materials is misleading.”

The image has also been used in other marketing materials, including in the commercial exhibit hall of the American Academy of Neurology annual meeting, which was held in New Orleans, April 23–26, 2012.

Eli Lilly has not yet issued a press statement in response to the Warning Letter.

Amyvid was approved by FDA in April 2012, but received a complete response letter from FDA in March 2011 because of concerns about how to review and interpret Amyvid scans. In response, Eli Lilly created a specific training program.