• Navidea Biopharmaceuticals Inc., of Dublin, Ohio, said results of a post-mortem brain tissue study using its investigational Fluorine-18-labeled beta-amyloid imaging agent, NAV4694, to compare performance characteristics of the NAV4694 to 11C-labeled Pittsburgh Compound-B, in control and Alzheimer's disease brain tissue concluded that, although the molecules share structural similarity, NAV4694 better differentiated amyloid deposition associated with Alzheimer's. Results were presented recently at the Alzheimer's Association International conference in Boston.