Whole-body biodistribution and radiation dosimetry of 18F-GE067: a radioligand for in vivo brain amyloid imaging.

Abstract

We have characterized the biodistribution and dosimetry of (18)F-3'-F-6-OH-BTA1 ((18)F-GE067), a newly developed radioligand to visualize and quantify amyloid burden, in healthy elderly human subjects. Six subjects (5 men and 1 woman; age range, 51-74 y) underwent dynamic whole-body PET/CT for 6 h after a bolus injection of (18)F-GE067. Source organs were delineated on PET/CT. Individual organ doses and effective doses were determined. No adverse events or clinically significant changes were observed. (18)F-GE067 is excreted predominantly through the hepatobiliary system. The gallbladder, upper large intestine, and small intestine are the organs with the highest absorbed dose (average, 287, 173, and 155 microGy/MBq, respectively). The mean effective dose was 33.8 +/- 3.4 microSv/MBq, a dose comparable to that of many other (18)F-labeled radiopharmaceuticals. The estimated effective dose of (18)F-GE067 for PET amyloid imaging was acceptable (class II-b defined by the World Health Organization), and relatively low variability between subjects was observed.