Navidea Biopharmaceuticals, a Dublin, Ohio-based biopharmaceutical company focused on precision diagnostic radiopharmaceuticals, has commenced enrollment at two sites participating in its phase II, open-label, safety and efficacy PET imaging study of [18F]NAV4694 for detection of cerebral β-amyloid plaque in subjects diagnosed with probable Alzheimer's disease (AD).

The open-label, multiple-center, non-randomized single dose, PET imaging study is designed to compare images from subjects with probable AD with similarly aged and young healthy volunteers. The two trial sites are currently enrolling subjects are Molecular NeuroImaging in New Haven, Conn., which dosed the first patient in the study, and the Alzheimer's Disease Center at Quincy Medical Center in Quincy, Mass.

"NAV4694 appears to exhibit the strengths of 11C PIB, but given that the ligand is labeled with 18F, it offers flexibility and is more practical to use,” said Danna Jennings, clinical research director, Molecular NeuroImaging. “The data at this point in the development suggest that NAV4694 shows favorable sensitivity, specificity and decreased white-matter uptake that may enable earlier Alzheimer's disease identification, better monitoring of disease progression, and easier scan interpretation."

Frederick Cope, senior vice president of pharmaceutical research and clinical development, Navidea, said, "Our ultimate goal is to provide an improved diagnostic tool with outstanding performance characteristics for physicians to aid in the diagnosis of AD, a disease expected to impact as many as 16 million Americans by 2050."

In addition to safety and efficacy objectives, the study also will measure the correlation between neuro-psychiatric test results with the amount of β-amyloid determined by the NAV4694 imaging.