UCB-J exhibits high free fraction (0.46 ± 0.02) and metabolizes at a moderate rate (39% ± 5% and 24% ± 3% parent remaining at 30 and 90 min) in plasma[3]. UCB-J displays high uptake and fast kinetics in the monkey brain[3]. When the animal is pretreated with UCB-J (150 μg/kg, iv), the whole brain SUV decreases to the same level as centrum semiovale, indicating the in vivo binding specificity of [ 18 F]7 to SV2A[4].